Gas-powered water guns and methods

ABSTRACT

The present invention generally relates to various water guns arranged to eject water by gas pressure. More particularly, the present invention relates to a water gun with a water chamber and a reaction chamber, where the water chamber receives and stores water therein and where a reaction chamber is in fluid communication with the water chamber, receives a reactant for generating gas by a chemical reaction, holds the gas, and supplies the gas directly or indirectly to the water chamber so that the gas increases pressure inside the water chamber and dispenses the water through a water outlet of the water gun on user commands by pressure difference generated by the gas between an interior of such a water chamber and atmosphere. A water gun of this invention may include a water chamber which receives and stores water therein, receives a reactant to generate gas by a chemical reaction, increases its pressure by the gas, and dispenses the water through a water outlet of such a water gun on user command by the above pressure difference. The present invention also relates to various methods of ejecting water using water guns by gas pressure. More particularly, a method of such an invention includes the steps of receiving and storing water in a water chamber, generating gas by at least one chemical reaction, and ejecting the water by the gas. Such water guns according to the present invention may include other sources of pressure such as conventional manual nozzles and/or hand air pumps. Such foregoing reaction chamber of this invention may also be arranged to be retrofit to conventional water guns.

FIELD OF THE INVENTION

The present invention generally relates to various water guns arranged to eject water by gas pressure. More particularly, the present invention relates to a water gun with a water chamber and a reaction chamber, where the water chamber receives and stores water therein and where a reaction chamber is in fluid communication with the water chamber, receives a reactant for generating gas by a chemical reaction, to hold the gas, and to supply such gas directly or indirectly to the water chamber so that the gas may increase pressure inside the water chamber and dispense the water through an outlet of the water guns on user commands by a pressure difference generated by the gas between an interior of such a water chamber and atmosphere. The present invention further relates to various methods of ejecting water using water guns by gas pressure. More particularly, a method of such an invention includes the steps of receiving and storing water in a water chamber, generating gas by at least one chemical reaction, and ejecting the water by the gas. The water guns of this invention may include other sources of pressure such as, e.g., conventional manual nozzles and/or hand air pumps. In addition, the foregoing reaction chamber may be retrofit to conventional water guns.

BACKGROUND OF THE INVENTION

Water guns have been popular toys for young children as well as juveniles during the summer. Users may manually squeeze triggers or nozzle handles of conventional water guns to eject or spray water stored in their water chambers. Upon finishing ejection of a preset amount of water which may generally be determined by a stroke volume of the nozzle, the triggers or handles are reciprocated by recoil mechanisms for a next cycle of ejection. Despite their simple configuration and operation, these conventional water guns suffer from a few drawbacks. For example, the users may eject water only while squeezing the triggers or handles. When the triggers reach ends of their reciprocating path, the users have to let go the triggers such that the triggers return to their initial position and the nozzles are refilled with water. Because it is impossible to eject water during these refilling periods, these water guns only allow intermittent ejection of water. In addition, linear velocities or flow rates of streams of ejected water of such water guns are generally user dependent. Accordingly, the users have only to squeeze the triggers or handles forcefully to obtain satisfactory results, which may easily tire fingers of the users.

Water guns are now equipped with air pumps. Users manually reciprocate handles of the air pumps to generate compressed air and increase pressure in water chambers of such water guns by supplying the compressed air thereto. Pressure difference or gradient generated between the water chambers and atmosphere allow the users to eject or spray water, simply by squeezing or pressing triggers which drive water through water outlets by the pressure difference. For example, FIG. 1A is a schematic diagram of a prior art water gun which includes a hand air pump for compressing air and ejecting water out of a water chamber by air pressure. A water gun 10 includes a water chamber 20 and an air pump 30. The water chamber 20 has a water outlet 21 and a conduit 22 between which a control valve 23 is disposed, where a trigger is operatively coupled to the control valve 23 such that squeezing the trigger opens the valve 23, while releasing such closes the valve 23. The air pump 30 includes a handle 31 connected to a piston 32 which in turn includes an opening 33 in which one-way valve 34 is disposed such that air inside the pump 30 is compressed as the user pushes the piston 32 into the pump 30, while air flows into the pump 30 as the user (or an elastic unit which is not shown in the figure) pulls the piston 32 away from the pump 30 (or to its original biased position). An exemplary one-way valve 34 shown in FIG. 1A includes a flap 34A which is arranged to open and close about a pivot 34B. Compressed air flows from the pump 30 to the water chamber 20 through conduits 36, 38 between which an additional control valve (or one-way valve) 37 may be disposed. FIG. 1B shows a schematic diagram of another prior art water gun including a hand air pump which is similar to that of FIG. 1A and an air chamber for storing compressed air. A water gun 10 includes a water chamber 20 and an air pump 30 which are similar to those of FIG. 1A. An air chamber 40 is disposed between the air pump 30 and water chamber 20, and connected thereto by conduits 36, 38, 41, 42 between which one or more control valves (or one-way valves) 37, 43 may be disposed. A trigger is also operatively coupled to one of the valves 37, 43 so that squeezing and releasing the trigger opens and closes the valve to eject and stop water, respectively. FIG. 1C shows a schematic diagram of yet another prior art water gun with a hand air pump similar to that of FIG. 1A and a pair of water chamber-air chamber assemblies. For example, a water gun 10 includes a first assembly of a first water chamber 20A and a first air chamber 40A as well as a second assembly of a second water chamber 20B and a second air chamber 40B, in which each chamber of the first and second assemblies is connected to adjacent chambers by various conduits 36A, 38A, 41A, 42A, 36B, 38B, 41B, 42B between which one or more control or one-way valves 37A, 43A, 37B, 43B may also be disposed. Each of such first and second assemblies also include a separate trigger which is in turn operatively coupled to one of such valves 37A, 43A, 37B, 43B. The water gun 10 also includes an air pump 30 similar to those of FIGS. 1A and 1B and arranged to supply compressed air to both air chambers 40A, 40B. By manipulating a proper trigger(s), the user may eject water from one or both water outlets 21A, 21B.

Although these air-powered water guns may allow the users to eject water continuously and may not easily tire the users, they have their own drawbacks. For example, air is highly compressible and, therefore, the users have to reciprocate the handles of the air pumps many times or more so as to generate compressed air enough to eject continuous streams of water which may last only a short period such as, e.g., 10 seconds or so. Although such water guns may continuously eject water, the pressure inside its water chamber also decreases gradually roughly in proportion with an amount of water ejected therefrom. Furthermore, the air-powered water guns still require the users to consume a significant amount of energy by pumping air thereinto.

Therefore, there is a need for water guns which may eject water continuously or intermittently without requiring significant work of the users and may eject water at relatively uniform velocities or flow rates over time.

SUMMARY OF THE INVENTION

The present invention generally relates to various water guns arranged to eject water by gas pressure. More particularly, the present invention relates to water guns capable of generating gas by a chemical reaction(s) and utilizing pressure of such gas to eject water from water chambers of such water guns.

In one aspect of the present invention, a gas-powered water gun is provided for dispensing water through at least one water outlet on an user command by a pressure difference developed by gas between an interior of the water gun and atmosphere. In one exemplary embodiment, the water gun may include at least one water chamber which is arranged to receive water, to store the water therein, to receive at least one reactant capable of generating the gas through at least one chemical reaction and developing the pressure difference, to have an airtight configuration to prevent leakage of the gas (or to minimize loss of the gas) therefrom (or to maintain the pressure difference therein), and then to dispense the water through the water outlet by the gas on the user command. In another exemplary embodiment, the water gun may include at least one water chamber including at least one water inlet and at least one reactant inlet each of which is arranged to receive water and at least one reactant therethrough, respectively. Such a reactant is arranged to generate the gas through at least one chemical reaction and to develop the above pressure difference. The water chamber is arranged to have an airtight configuration to prevent leakage of the gas or to minimize loss of the gas therefrom (or to maintain the pressure difference therein), and to dispense the water through the water outlet by the gas on the user command. In another exemplary embodiment, the water gun includes at least one water chamber and at least one reaction chamber. The water chamber is arranged to receive water and to store the water therein, whereas the reaction chamber is arranged to be in fluid communication with the water chamber, to receive at least one reactant which is arranged to generate the gas by at least one chemical reaction, and to supply the gas either directly or indirectly to the water chamber to dispense the water through the water outlet by the gas on the user command. In another exemplary embodiment, the water gun includes at least one water chamber, at least one reaction chamber, and at least one gas chamber. The water chamber is similarly arranged to receive water and to store the water therein, and the reaction chamber is also arranged to be in fluid communication with the water chamber, to receive at least one reactant arranged to generate the gas through at least one chemical reaction, and to supply the gas either directly or indirectly to the water chamber to dispense the water through the water outlet by the gas on the user command. The gas chamber is generally arranged to be in fluid communication with the reaction chamber, to receive at least a portion of the gas from the reaction chamber when pressure in the reaction chamber exceeds pressure in the gas chamber, and then to supply the portion of the gas to the water chamber when pressure in the water chamber falls below the pressure in the gas chamber.

The foregoing gas-powered water guns may include various reactant chambers for supplying reactants to various chambers thereof. In one exemplary embodiment, the water gun includes at least one water chamber and at least one reactant chamber. Such a water chamber is arranged to receive water, to store the water therein, to receive at least one reactant capable of generating the gas by at least one chemical reaction and developing the pressure difference, to have an airtight configuration to prevent leakage of the gas (or to minimize loss of such gas) therefrom (or to maintain the pressure difference therein), and to dispense the water through the water outlet on the user command by such gas. The reactant chamber is arranged to couple with the water chamber, to store multiple doses of the reactant(s), and to supply each (or at least one) dose of such reactant(s) to the water chamber. In another exemplary embodiment, such a water gun includes at least one water chamber and at least one reactant chamber. The water chamber includes at least one water inlet and at least one reactant inlet each arranged to receive water and at least one reactant therethrough, respectively, into such a water chamber. The reactant is arranged to generate the gas through at least one chemical reaction and to develop the pressure difference. The water chamber is further arranged to have an airtight configuration to prevent leakage of the gas (or to minimize loss of the gas) therefrom (or to maintain the pressure difference therein) and to dispense the water through the water outlet by the gas on the use command. The reactant chamber is arranged to couple with the water chamber, to store multiple doses of the reactant, and to supply each (or at least one) dose of the reactant to the water chamber. In another exemplary embodiment, such a water gun may include at least one water chamber, at least one reaction chamber, and at least one reactant chamber. The water chamber is similarly arranged to receive water and to store the water therein. The reaction chamber is typically arranged to be in fluid communication with the water chamber, to receive at least one reactant arranged to generate the gas through at least one chemical reaction, and to supply the gas either directly or indirectly to the water chamber so as to dispense the water through the water outlet by the gas on the user command. The reactant chamber is arranged to be coupled to the reaction chamber, to store multiple doses of such a reactant(s), and to supply the reaction chamber with each (or at least one) dose of the reactant(s). In another exemplary embodiment, the water gun also includes at least one water chamber, at least one reaction chamber, at least one gas chamber, and at least one reactant chamber. The water chamber is arranged to receive water and to store the water therein, while the reaction chamber is arranged to be in fluid communication with the water chamber, to receive at least one reactant which is arranged to generate the gas through at least one chemical reaction, and to supply the gas either indirectly or indirectly to the water chamber in order to dispense the water through the water outlet by the gas on the user command. The gas chamber is arranged to be in fluid communication with the above reaction chamber, to receive at least a portion of the gas from the reaction chamber when pressure in such a reaction chamber exceeds pressure of the gas chamber, and then to supply the portion of the gas to the water chamber as pressure in the water chamber falls below the pressure of the gas chamber. The reactant chamber is arranged to couple with the reaction chamber, to store multiple doses of the reactant(s), and to supply the reaction chamber with each (or at least one) dose of such reactant(s).

Embodiments of this aspect of the invention may include one or more of the following features.

The chambers of the above water gun may be arranged to have various shapes and/or sizes. Each chamber may be provided in a single or multiple arrangements and disposed in almost any part of the water gun. The water gun may include an optional hand air pump arranged to manually compress air and to utilize such along with the gas to dispense the water out of the water gun. Such a hand air pump may be arranged in parallel with the reaction chamber and/or gas chamber or, in the alternative, in series with the reaction chamber and/or gas chamber, e.g., in its upstream and/or downstream. In addition, the trigger of the water gun may also be operatively coupled to the water chamber, reaction chamber, and/or gas chamber so that the user command may be delivered to such chamber(s). The water gun may include at least one press-regulating valve and/or one-way valve in order to prevent or minimize loss of gas or pressure thereof during delivering such gas between the chambers. Such chambers may be arranged to perform their operations either manually, e.g., on the user command, or automatically. One or more of such chambers may include a safety valve so as to prevent excessive pressure buildup therein. The water gun may include multiple reaction, gas, and/or reactant chambers which are arranged in a parallel and/or series configuration and which may have identical or different shapes and/or sizes. Filters may be incorporated in an upstream or downstream of such chambers to prevent undesirable solid particles or gels from dogging the water outlet. The water gun may include a control unit which may control operations of various chambers, e.g., by monitoring pressures in any of such chambers, a water level in the water chamber, a reactant level in the reaction chamber and/or reactant chamber, temperatures in any of such chambers, and the like, by supplying the water and/or gas to different chambers, by generating various alarm signals to inform the user, e.g., of refilling the reactant and/or water, discharging the byproducts, and the like.

In another aspect of the present invention, a reaction chamber is provided to generate gas for a gas-powered water gun for dispensing water from a water chamber through a water outlet on an user command by a pressure difference developed by the gas between an interior of the water gun and atmosphere. In one exemplary embodiment, such a reaction chamber may include a body, at least one reactant inlet, and at least one gas outlet. The body is preferably made to be airtight such that air or gas does not flow thereinto or therefrom except designated conduits, e.g., various inlets or outlets. The reactant inlet is formed on or through the body and arranged to receive therethrough at least one reactant arranged to generate the gas by at least one chemical reaction. The gas outlet is defined on or through the body and arranged to supply therethrough such gas to the interior of the water gun to generate the pressure difference. In another exemplary embodiment, the reaction chamber includes a similar airtight body, at least one reactant inlet, and at least one gas outlet. The reactant inlet is formed on the body and arranged to operate between an open position and a closed position so that the inlet is open to an exterior of the water gun and closed to the body in the open position to be loaded with at least one reactant arranged to generate the gas by at least one chemical reaction and that the inlet is closed to the exterior of the water gun and open to the body in the closed position so as to transport the reactant into the body while preventing or minimizing loss of the gas from the body to the exterior of the water gun. The gas outlet is formed on the body and arranged to supply therethrough the gas to the interior of the water gun in order to generate the pressure difference. In yet another exemplary embodiment, the reaction chamber includes a similar airtight body, at least one reactant inlet, at least one gas outlet, and at least one water inlet. The reactant inlet is defined on the body and arranged to receive therethrough at least one reactant arranged to generate the gas through at least one chemical reaction into such a body. The gas outlet is formed on the body and arranged to supply therethrough the gas to the interior of the water gun to generate the pressure difference. The water inlet is formed on the body and arranged to receive therethrough water which may be required as a reactant or as a medium for the foregoing chemical reaction. In another exemplary embodiment, the reaction chamber may include a similar airtight body, at least one reactant inlet, at least one gas outlet, and at least one discharge outlet. The reactant inlet is also formed on the body and arranged to receive therethrough at least one reactant which is arranged to generate the gas by at least one chemical reaction into the body. The gas outlet is also defined on the body and arranged to supply therethrough the gas to the interior of the water gun to generate the pressure difference. The discharge outlet is also formed on the body and arranged to discharge therethrough at least one byproduct and/or undesirable material formed by the chemical reaction.

Embodiments of this aspect of the invention may include one or more of the following features.

The foregoing reaction chamber may be arranged to have various shapes and/or sizes, to be provided in any number, and to be disposed in almost any location of the water gun. When the water gun includes an optional hand air pump, the reaction chamber may be disposed in parallel with the air pump or to be in series with the air pump by being disposed in the upstream or downstream of the air pump. The trigger of the water gun may be operatively coupled to the reaction chamber such that the water gun dispenses water as the user sends the user command to the reaction chamber. The one-way valve and/or pressure-regulating valve may be incorporated into the reaction chamber to prevent or minimize loss of gas or gas pressure therefrom. The reaction chamber may be arranged to perform operations either manually on the user command or automatically. Examples of such operations may include, but not be limited to, when to generate the gas, when to supply such gas to any of the above chambers, when to reload the reactants to the reaction chamber, and the like. The safety valve may also be incorporated into the reaction chamber to prevent excessive pressure buildup. When multiple reaction chambers are incorporated, they may be arranged in a parallel or series configuration or may have the same or different shapes and/or sizes. In addition, a filter may be disposed in the upstream or downstream of the reaction chamber to prevent solid particles from leaving reaction chamber and clogging the water outlet of the water gun. The reaction chamber may include at least one sensor for monitoring a water level in the water chamber and stopping gas supply thereto when the water level is below a preset level or when no water remains therein. When the reactant requires water for the gas-generating chemical reaction as one of the reactants or as a medium the, water may be supplied from the water chamber either manually or automatically or, in the alternative, from an external water source. The gas generated in the reaction chamber may be delivered to the interior of the water gun examples of which may include, but not be limited to, the foregoing water chamber, reaction chamber, gas chamber, and the like.

In another aspect of the present invention, a reactant chamber is provided to store at least one reactant capable of generating gas by at least one chemical reaction and to supply the reactant to at least one gas-generating chamber of a water gun for dispensing water through a water outlet by the gas on an user command through a pressure difference developed by the gas between an interior of the water gun and atmosphere. In one exemplary embodiment, the reactant chamber includes a body arranged to store multiple doses of the reactant, and at least one loading unit coupled to such a body and arranged to transport at least one dose of the reactant from the body of the reactant chamber to the gas-generating chamber. In another exemplary embodiment, the reactant chamber may include a similar body as well as at least one loading unit coupled to the body and arranged to transport at least one dose of the reactant from the body of the reactant chamber to the gas-generating chamber. The loading unit is arranged to operate between an open position and a closed position so that the loading unit is closed to the gas-generating chamber and open to an exterior of the water gun in such an open position to prevent leakage of the gas therefrom while loading the reactant into the reactant chamber, and that the loading unit is open to the gas-generating chamber and closed to the exterior of the water gun in the closed position to prevent or at least minimize loss of the gas therefrom while transporting or loading the dose of the reactant to the gas-generating chamber. In another exemplary embodiment, the reactant chamber includes a body and at least one loading unit. Such a body is arranged to store multiple doses of different reactants which are arranged to react with each other and to generate the gas through at least one chemical reaction. The loading unit is arranged to couple with the body and to transport each (or at least one) dose of each of the reactants in a preset ratio from the body to the gas-generating chamber.

Embodiments of this aspect of the invention may include one or more of the following features.

Such a reactant chamber may be arranged to have any shapes and/or sizes, to be provided in any number, and to be disposed in any location of the water gun. The reactant chamber may perform its operations manually on the user command or automatically, where examples of the operations may include, but not be limited to, loading the reactant into the reactant chamber, transporting the reactant into the gas-generating chamber, and so on. In addition, such loading and transporting operations may be operatively coupled so that, when the reactant is transported into the gas-generating chamber, the same or similar number or amount of such a reactant is loaded to the reactant chamber. When multiple reactant chambers are used, they may be arranged in a parallel or series configuration, and they may have the identical configuration or different configurations. The reactant chamber may include various actuators arranged to transport the reactant to the gas-generating chamber, where examples of such actuators may include, but not be limited to, conventional dispenser for reactant pellets and/or solution, conventional solid transport mechanisms for reactant powder, and so on. The reactant chamber may also include various handles to activate the actuators. In addition, such handles and/or actuators may include recoil mechanisms so that the handles and/or actuators may be moved to their initial positions after such loading and/or transporting. The reactant chamber may also include retainers shaped and sized to retain the reactant and/or a container thereof. The reactant chamber may also be arranged to supply the reactant to the gas-generating chamber which may be the above reaction chamber, water chamber, gas chamber, and the like.

In another aspect of the present invention, a gas chamber is provided to store gas generated by at least one reactant by its chemical reaction and to supply such gas to at least one gas-generating chamber of a water gun arranged to dispense water through a water outlet on an user command by a pressure difference developed by such gas between an interior of the water gun and atmosphere. In one exemplary embodiment, such gas chamber may include a body, at least one gas inlet, and at least one gas outlet. The body of such a gas chamber is preferably arranged to be airtight to prevent loss of the gas or its pressure. The gas inlet is defined on the body and to transport the gas into the body therethrough, while the gas outlet is defined on the body and to transport the gas to the interior of the water gun to generate the foregoing pressure difference. In another exemplary embodiment, the gas chamber includes a body, at least one gas inlet, and at least one gas outlet. The body is arranged to be airtight and to change its volume in proportion to an amount of the gas stored therein. The gas inlet is arranged to be defined on the body and to transport such gas into the body therethrough, while the gas outlet is arranged to be defined on the body and to transport such gas to the interior of the water gun to generate the pressure difference.

Embodiments of this aspect of the invention may include one or more of the following features.

Such a gas chamber may be arranged to have any shapes and/or sizes, to be provided in any number, and to be disposed in any location of the water gun. When the water gun includes a hand air pump, the gas chamber may be arranged to be in parallel with the air pump or in series with the pump by being placed in its upstream or downstream to perform its operations therewith. The trigger of the water gun may be operatively coupled to the gas chamber such that the user command is delivered to the gas chamber. The gas chamber may also be arranged to perform various operations manually on the user command or automatically, where examples of the operations may include, but not be limited to, storing such gas therein, supplying the gas to the interior of the water gun which may be another chamber of the water gun operatively associated with dispensing water out of the water gun, and the like. When multiple gas chambers are used, they may be arranged in a parallel or series configuration, and they may have the identical or different configurations. At least one pressure-regulating valve or one-way valve may be incorporated in the upstream, in the downstream or inside the gas chamber to prevent or minimize loss of such gas and/or gas pressure from the gas chamber. At least one safety valve may also be to prevent excessive pressure buildup inside the gas chamber. In addition, a filter may be incorporated thereto to prevent solid particles or gels from leaving gas chamber and clogging the water outlet of the water gun. The gas chamber may include at least one sensor for monitoring a water level in the water chamber and stopping the gas supply thereto when the water level is low or there is no sufficient water in the water chamber. The gas chamber may be made elastic, i.e., made of an elastic material or, in the alternative, made of a non- or semi-elastic material but arranged to have an elastic configuration. Such an elastic gas chamber may be arranged to indicate a pressure and/or volume therein. The gas chamber may also be arranged to directly or indirectly supply the gas to the the interior of the water gun which may be the above water chamber, reaction chamber, and the like.

In another aspect of the present invention, various reactants are provided to generate the gas through at least one chemical reaction for a gas-powered water gun to dispense water from a water chamber through a water outlet by a pressure difference developed by the gas between an interior of the water gun and atmosphere. In one exemplary embodiment, the reactant may include at least one chemical compound arranged to be formed as a pellet, powder, and/or its solution and to generate the gas by at least one chemical reaction. In another exemplary embodiment, the reactant may include at least one compound arranged to be formed as a pellet, powder, and/or its solution and to generate the gas by at least one chemical reaction when the reactant is dissolved or mixed with water. In another exemplary embodiment, such a reactant may include at least one compound arranged to be formed as a pellet, powder, and/or its solution and to generate the gas by at least one chemical reaction as well as at least one external layer arranged to enclose at least a substantial part of such a reactant pellet, powder, and/or its solution. In another exemplary embodiment, the reactant may also include at least one compound arranged to be encapsulated (or microencapsulated) to have a preset solubility and to generate the gas by the chemical reaction at a reaction rate which is at least partly determined by the solubility. In another exemplary embodiment, the reactant may include multiple compounds arranged to be formed as a pellet, powder, and/or their solution and to generate the gas by at least one chemical reaction. In another exemplary embodiment, the reactant may include multiple compounds arranged to be formed as a pellet, powder, and/or their solution and to generate the gas by at least one chemical reaction when mixed together, and at least one divider arranged to be disposed between at least two of the compounds to segregate at least two of such compounds and to prevent at least two of such compounds from contacting each other. In another exemplary embodiment, the reactant may include multiple compounds arranged to be formed as a pellet, powder, and/or their solution and to generate the gas through at least one chemical reaction, and at least one external layer arranged to enclose at least a substantial portion of at least one of such compounds. In another exemplary embodiment, the reactant may also include multiple compounds arranged to be formed as a pellet, powder, and/or their solution, where at least one of the compounds is arranged to be encapsulated (or microencapsulated) to exhibit a preset solubility and where such compounds are arranged to generate the gas by at least one chemical reaction at a reaction rate which is at least partly determined by such a solubility.

Embodiments of this aspect of the invention may include one or more of the following features.

The reactant may be shaped and/or sized in any configurations as long as it may generate the gas in the gas-generating chamber. Thus, such a reactant may be formed as a pellet, powder, and/or solution thereof. The reactant may also be arranged to generate such as when a single reactant may be disposed in the gas-generating chamber when, e.g., exposed to air, mixed with water or a medium, shaken, disposed above a preset temperature and/or pressure, and so on. Multiple reactants may be arranged to generate such gas, e.g., when multiple reactants are mixed together, when at least one of the reactants is exposed to air, when at least one reactant is mixed with water or another medium, when shaken, when such reactants are disposed above a preset pressure and/or temperature, and the like. Reactant pellets may further be structured to facilitate dissolution in water or another medium by, e.g., forming apertures, having a porous structure such as those of granules and/or loosely bound chunks, providing protrusions or indentations thereto to increase their surface areas, and so on. The reactant may be capsuled and/or microcapsuled. For example, such reactant pellets may be coated, encapsuled, and/or microencapsulated, particles of reactant powder may be coated, capsuled, and/or microencapsulated, reactant solution may be stored in capsules and/or other containers, and the like. The reactant pellets and/or capsules may include multiple chemical compounds segregated in different regions thereof. For example, layers of the compounds may be horizontally, vertically, and/or radially arranged. Alternatively, each layer may be arranged to include multiple compounds.

In another aspect, a method is provided for dispensing water from a gas-powered water gun. In one exemplary embodiment, such a method may include the steps of generating gas through at least one chemical reaction, increasing pressure of an interior of the water gun by the gas, and dispensing the water from the water gun by the gas pressure. In another exemplary embodiment, such a method includes the steps of storing water in the water gun, generating gas by at least one chemical reaction, increasing pressure in a pressure-driving chamber of the water gun by the gas, developing pressure difference between the pressure-driving chamber and atmosphere, and dispensing the water from the water gun by the pressure difference.

Embodiments of this aspect of the invention may include one or more of the following features.

The foregoing chambers may serve for various purposes. For example, the water chamber or another separate chamber may be used as the gas-generating chamber, whereas the water chamber or another chamber and/or conduit in fluid communication with the water chamber or its water may be used as the pressure-driving chamber. Excessive pressure buildup in any of the foregoing chambers may be avoided by incorporating a safety valve thereto.

In another aspect, a method is provided for dispensing water from a gas-powered water gun which includes a water chamber for storing water therein, a gas-generating chamber for generating gas, and a pressure-driving chamber to drive water out of the water chamber by the gas or pressure thereof. In one exemplary embodiment, the method includes the steps of storing water in the water chamber, generating gas by at least one chemical reaction in the gas-generating chamber, increasing pressure in the pressure-driving chamber by the gas, and then dispensing the water from the water chamber by such pressure. In another exemplary embodiment, such a method may include the steps of storing water in the water chamber, providing at least one reactant to the gas-generating chamber, generating gas by at least one chemical reaction of the reactant, increasing pressure in the pressure-driving chamber by the gas, developing pressure difference between the pressure-driving chamber and atmosphere, and dispensing the water from the water chamber by such pressure difference.

Embodiments of this aspect of the invention may include one or more of the following features.

The foregoing chambers may serve for various purposes. For example, the water chamber or another separate chamber may be used as the gas-generating chamber, whereas the water chamber or another chamber and/or conduit in fluid communication with the water chamber or its water may be used as the pressure-driving chamber. Excessive pressure buildup in any of the foregoing chambers may be avoided by incorporating a safety valve thereto. When the water gun includes an optional air pump, the gas-generating chamber and/or pressure-driving chamber may be arranged in parallel with such a pump or in series with (e.g., in its upstream or downstream) the pump.

In another aspect, a method is provided for generating gas by at least one chemical reaction to dispense water from a gas-powered water gun. In one exemplary embodiment, the method includes the steps of providing at least one reactant in a gas-generating chamber of the water gun, generating the gas through at least one chemical reaction of the reactant, and then dispensing the water from the water gun by the gas. In another exemplary embodiment, the method includes the steps of providing multiple reactants in a gas-generating chamber of the water gun, mixing or contacting the reactants in the gas-generating chamber, generating the gas by at least one chemical reaction between or among such reactants, and dispensing the water from the water gun by the gas or its pressure. In another exemplary embodiment, the method may include the steps of providing multiple reactants, loading the reactants in a preset ratio in a gas-generating chamber of the water gun, mixing such reactants in the gas-generating chamber, generating the gas by at least one chemical reaction among or between the reactants, and then dispensing the water out of the water gun by the gas or its pressure. In another exemplary embodiment, the method may include the steps of providing at least one reactant in a gas-generating chamber of the water gun, adding water into the gas-generating chamber, dissolving the reactant in the water to obtain dissolved molecules of the reactant, generating the gas by at least one chemical reaction between or among the dissolved molecules, and then dispensing the water from the water gun by the gas. In another exemplary embodiment, the method includes the steps of providing at least one reactant to a gas-generating chamber of the water gun, providing water into such a gas-generating chamber, generating the gas by at least one chemical reaction between the reactant and water, and dispensing the water from the water gun by the gas.

In yet another exemplary embodiment, the method includes the steps of providing at least one reactant to a gas-generating chamber of the water gun, generating the gas by at least one chemical reaction of the reactant, arranging the gas-generating chamber to be airtight, adjusting or controlling an extent of the reaction by controlling a pressure, temperature, and/or concentration of the reactant in the gas-generating chamber, controlling pressure in the gas-generating chamber by the extent of the reaction, and dispensing the water from the water gun by the gas. In another embodiment, such a method includes the steps of providing at least one reactant in a gas-generating chamber of the water gun, generating the gas by at least one chemical reaction of the reactant, monitoring a water level of a water chamber of the water gun, supplying the gas to a pressure-driving chamber of the water gun in order to dispense the water from the water gun by the gas, and terminating supply of the gas to such a pressure-driving chamber when the water level of the water chamber falls below a preset level. In another exemplary embodiment, the method includes the steps of providing at least one reactant to a gas-generating chamber of the water gun, generating the gas through at least one chemical reaction of the reactant, dispensing the water out of the water gun by such gas, and discharging at least one byproduct from the chemical reaction from the gas-generating chamber.

Embodiments of this aspect of the invention may include one or more of the following features.

The gas-generating chamber is arranged to be airtight except designated inlets and outlets so as to minimize loss of the gas therefrom. Such a gas-generating chamber may be the foregoing water chamber or a separate reaction chamber. When the water gun includes an optional air pump, the gas-generating chamber may be arranged in parallel with the air pump or in series (e.g., in its upstream or downstream) with such a pump. Optional safety valves may be incorporated into the water chamber, pressure-driving chamber, and/or gas-generating chamber so as to avoid excessive pressure buildup therein. When the chemical reaction requires water for generating the gas, water may be provided by the water chamber or an external water source into the gas-generating chamber. When the chemical reaction produces unfavorable byproducts, they may be discharged from the gas-generating chamber manually, when concentration and/or volume of such byproducts exceeds a preset level, whenever a reactant is loaded into the gas-generating chamber, and so on. The gas-generating chamber may also be arranged to terminate supplying the gas to the water chamber, e.g., as the water chamber is low in water or has no water therein, during refilling water to the water chamber, when a conduit leading to a water outlet of the water gun has no water therein, and the like.

In another aspect, a method is provided for supplying gas generated by at least one chemical reaction to a gas-powered water gun for dispensing water therefrom. In one exemplary embodiment, such a method includes the steps of generating the gas in a gas-generating chamber, storing at least a portion of the gas in a separate gas chamber, thereby increasing a total amount of such gas present in the water gun, and then dispensing the water from the water gun by the gas. In another exemplary embodiment, such a method may include the steps of generating the gas in a gas-generating chamber, receiving and storing at least a portion of the gas in an elastic chamber, thereby increasing an amount of the gas available inside the water gun and minimizing (or reducing) a temporal variation in pressure of the gas inside the water gun, and dispensing the water from the water gun by the gas. In another exemplary embodiment, such a method may include the steps of arranging at least a portion of a gas-generating chamber to be made of elastic materials or to have an elastic configuration, generating the gas in the gas-generating chamber, thereby increasing a total amount of the gas available in the gas-generating chamber and minimizing (or reducing) a temporal variation in pressure of the gas in such a gas-generating chamber, and dispensing the water from such a water gun by the gas. In yet another exemplary embodiment, a further method includes the steps of arranging at least a portion of a water chamber to be made of an elastic material or to have an elastic configuration, generating the gas in a gas-generating chamber, supplying the gas to the water chamber, thereby increasing a volume of the water chamber according to (or in proportion to) a total amount of the gas in the water chamber and thereby minimizing (or reducing) a temporal variation in pressure of the gas in the water chamber, and dispensing the water from the water gun by the gas.

Embodiments of this aspect of the invention may include one or more of the following features.

The elastic chamber may be arranged to be airtight except designated inlets and outlets so that loss of the gas may be prevented or minimized. The elastic chamber may be arranged to be in parallel with the gas-generating chamber or, alternatively, in series with (e.g., in its upstream or downstream) the gas-generating chamber. When the water gun includes an optional air pump, the elastic chamber may also be arranged to be in parallel with the air pump or, in the alternative, in series with (e.g., in its upstream or downstream) such a pump.

In another aspect, a method is provided for maintaining gas pressure and for minimizing a loss thereof in a gas-powered water gun while loading at least one reactant capable of generating gas by at least one chemical reaction to a gas-generating chamber of the gun. In one exemplary embodiment, the method may include the steps of coupling a loading unit to a gas-generating chamber, opening the loading unit to atmosphere while isolating or closing such a gas-generating chamber from atmosphere, providing the loading unit with the reactant, isolating or closing the loading unit from atmosphere while opening the loading unit to the gas-generating chamber, transporting the reactant or one dose thereof to the gas-generating chamber, thereby minimizing loss of the gas from the gas-generating chamber to atmosphere during the transporting, generating the gas in the gas-generating chamber, supplying the gas to a pressure-driving chamber, and dispensing water from the water gun by the gas.

Embodiments of this aspect of the invention may include one or more of the following features.

The elastic chamber may be arranged to be airtight except designated inlets and outlets so as to minimize loss of gas and/or its pressure therefrom. The elastic chamber may be disposed in series with (e.g., in an upstream or downstream of the gas-generating chamber and/or in parallel with such a chamber. When the water gun includes an optional air pump, the elastic chamber may be arranged in series or parallel with such an air pump.

In yet another aspect, a method is provided for maintaining gas pressure and minimizing loss of such gas or its pressure in a gas-powered water gun, while loading at least one reactant capable of generating gas by at least one chemical reaction to a gas-generating chamber of the water gun. Such a method generally includes the steps of coupling a loading unit to a gas-generating chamber, opening the loading unit to atmosphere, isolating the gas-generating chamber from atmosphere, providing such a loading unit with the reactant, isolating the loading unit from atmosphere, opening (or communicating) the loading unit to the gas-generating chamber, transporting such a reactant to such a gas-generating chamber, thereby minimizing loss of the gas from the gas-generating chamber into atmosphere during the transporting, generating the gas in the gas-generating chamber, supplying the gas to a pressure-driving chamber, and dispensing water from the water gun by the gas.

As used herein, a term “gas-generating chamber” generally refers to any chamber arranged to receive at least one reactant capable of generating gas through at least one chemical reaction thereof and to generate the gas through the chemical reaction therein. Such a “gas-generating chamber” may be provided as a separate chamber or, alternatively, other chambers may be arranged to serve as the “gas-generating chamber” as well. A gas-powered water gun of the present invention may include a single or multiple “gas-generating chambers” depending upon detailed configuration thereof. It is noted that a term “reaction chamber” is interchangeably used with the “gas-generating chamber” throughout this description unless otherwise specified.

A “pressure-driving chamber” generally refers to any chamber of which the pressure may be increased by gas generated by the above reactant through the chemical reaction. Similar to the gas-generating chamber, such a “pressure-driving chamber” may be provided as a separate chamber or, alternatively, other chambers may be arranged to serve as the “pressure-driving chamber” as well. A gas-powered water gun of this invention may include a single or multiple “pressure-driving chambers” depending upon detailed configuration thereof. It is noted that the “pressure-driving chamber” may or may not be a chamber from which water is dispensed by the pressure thereof.

As used herein, a “conduit” refers to a path, pathway or passageway for gases and liquids. Accordingly, a “conduit” may have any internal and/or external shape and/or size as long as it allows such gases and liquids to flow from one to the other end thereof.

In addition, a term “elastic chamber” means either a chamber which is made of and/or includes an elastic material or a chamber which is not made of and/or includes elastic materials but which may exhibit elastic behavior due to its configurational characteristics.

Unless otherwise defined in the following specification, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although the methods or materials equivalent or similar to those described herein can be used in the practice or in the testing of the present invention, the suitable methods and materials are described below. All publications, patent applications, patents, and/or other references mentioned herein are incorporated by reference in their entirety. In case of any conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

Other features and advantages of the present invention will be apparent from the following detailed description, and from the claims.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1A is a schematic diagram of a prior art water gun with a hand air pump for compressing air and for ejecting water out of a water chamber by air pressure;

FIG. 1B is a schematic diagram of another prior art water gun including a hand air pump similar to that of FIG. 1A and an air chamber for storing compressed air,

FIG. 1C is a schematic diagram of yet another prior art water gun with a hand air pump similar to that of FIG. 1A and a pair of water chamber-air chamber assemblies;

FIG. 2A is a schematic diagram of an exemplary water gun with a water chamber for receiving reactants and generating gas therein according to the present invention;

FIG. 2B is a schematic diagram of an exemplary water gun similar to that of FIG. 2A and having a separate reactant chamber for storing reactants and providing such to a water chamber to generate gas therein according to the present invention;

FIG. 2C is a schematic diagram of an exemplary water gun having a water chamber for storing water and a separate reaction chamber for receiving reactants and generating gas therein according to the present invention;

FIG. 2D is a schematic diagram of an exemplary water gun similar to that of FIG. 2C and having a separate reactant chamber for storing reactants and supplying such to the reaction chamber so as to generate gas therein according to the present invention;

FIG. 3A is a schematic diagram of an exemplary water gun with a water chamber for receiving reactants and generating gas therein and a separate gas chamber for storing the gas according to the present invention;

FIG. 3B is a schematic diagram of an exemplary water gun having a water chamber for storing water and a separate gas chamber for receiving reactants, generating gas therein, and storing such gas therein according to the present invention;

FIG. 3C is a schematic diagram of an exemplary water gun similar to that of FIG. 3A and having a separate reactant chamber for storing reactants and supplying such to the water chamber so as to generate gas therein according to the present invention;

FIG. 3D is a schematic diagram of an exemplary water gun similar to that of FIG. 3B and having a separate reactant chamber for storing reactants and supplying such to the gas chamber in order to generate gas therein according to the present invention;

FIG. 3E is a schematic diagram of an exemplary water gun having a water chamber for storing water, a separate reaction chamber for receiving reactants and generating gas as well as a separate gas chamber for storing gas therein according to the present invention;

FIG. 3F is a schematic diagram of an exemplary water gun similar to that of FIG. 3E and having a separate reactant chamber for storing reactants and supplying such to the reaction chamber so as to generate gas therein according to the present invention;

FIG. 4A is a schematic diagram of an exemplary gas-generating reactant pellet which includes two longitudinally arranged reactants (or layers) according to the present invention;

FIG. 4B is a schematic diagram of an exemplary gas-generating reactant pellet which includes three longitudinally arranged reactants (or layers) according to the present invention;

FIG. 4C is a schematic diagram of an exemplary gas-generating reactant pellet which includes two longitudinally arranged reactants (or layers) as well as an interlayer divider placed therebetween according to the present invention;

FIG. 4D is a schematic diagram of an exemplary gas-generating reactant pellet which includes two radially arranged reactants (or layers) according to the present invention;

FIG. 4E is a schematic diagram of an exemplary gas-generating reactant pellet which includes three radially arranged reactants (or layers) according to the present invention;

FIG. 4F is a schematic diagram of an exemplary gas-generating reactant pellet which includes two radially arranged reactants (or layers) and an interlayer divider placed therebetween according to the present invention;

FIG. 4G is a schematic diagram of an exemplary gas-generating reactant pellet similar to those of FIGS. 4A to 4C and defining a center aperture according to the present invention;

FIG. 4H is a schematic diagram of an exemplary gas-generating reactant pellet similar to those of FIGS. 4D to 4F and defining a center aperture according to the present invention;

FIG. 4I is a schematic diagram of an exemplary reactant pellet similar to those of FIGS. 4A to 4C and 4G and including an exterior coated layer according to the present invention; and

FIG. 4J is a schematic diagram of an exemplary reactant pellet similar to those of FIGS. 4D to 4F and 4H and including an exterior coated layer according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention generally relates to gas-powered water guns for dispensing water by gas obtained through a chemical reaction inside the water guns. More particularly, such an invention relates to a water gun having a water chamber which is arranged to receive and store water therein, to receive a reactant which generates gas by a chemical reaction therein, to retain the gas, and then to dispense water out of the water gun on user commands by pressure difference developed by the gas between the water chamber and atmosphere. The present invention also relates to a water gun including a water chamber and a separate gas-generating chamber. The water chamber is arranged to receive and store water therein, and the gas-generating chamber is arranged to receive a reactant which generates gas by a chemical reaction therein, to retain the gas, and to supply the gas indirectly or directly to a pressure-driving chamber so that the gas may increase pressure inside the pressure-driving chamber and dispense water out of the water chamber on user commands through pressure difference generated by the gas between such a pressure-driving chamber and atmosphere. Such a pressure-driving chamber may be the water chamber or a separate chamber physically distinct from the water chamber. The present invention also relates to various methods of dispensing water from water guns by gas pressure. More particularly, a method of such an invention includes the steps of receiving and storing water in a water chamber, generating gas by at least one chemical reaction, and dispensing water by pressure generated by such gas.

Gas-powered water guns of the present invention may be constructed according to various embodiments. Each of such water guns generally includes at least one water chamber to store water therein, at least one gas-generating chamber or reaction chamber to generate at least one type of gas therein through at least one chemical reaction, and at least one pressure-driving chamber to increase its internal pressure by the gas and to dispense water therefrom or from the water chamber. Though such three chambers are essential elements of the gas-powered water guns of the present invention, the above three chambers do not have to be provided as physically separate chambers. For example, a single water chamber may be arranged to serve as the gas-generating chamber and the pressure-driving chamber. Alternatively, the water gun may include the water chamber and the gas-generating chamber (or pressure-driving chamber) which may further serve as the pressure-driving chamber (or gas-generating chamber). As will be explained in greater detail below, the water guns of the present invention may also include other optional chambers such as, e.g., a reactant chamber for storing and transporting a reactant to the gas-generating chamber, elastic chamber for storing the gas therein and reducing fluctuation in gas pressure, and the like. Following figures illustrate exemplary embodiments of various gas-powered water guns of the present invention. It is noted, however, that such figures and/or accompanied descriptions are intended to illustrate and not to limit the scope of this invention.

In one aspect of the present invention, gas-powered water guns may be provided to dispense water through their water outlets on user commands through pressure difference developed by gas between interiors of the water guns and atmosphere. FIGS. 2A and 2B exemplify various water guns including water chambers which may also serve as gas-generating and pressure-driving chambers.

FIG. 2A is a schematic diagram of an exemplary water gun with a water chamber for receiving reactants and generating gas therein according to the present invention. An exemplary water gun 11 may typically include a water chamber 20, a water inlet (not shown in the figure), a water outlet 21, at least one conduit 22, a control valve 23, at least one reactant inlet 52, a trigger, and so on. The water chamber 20 is typically arranged to receive water through the water inlet from an external source and to store water therein. The reactant inlet 52 may be disposed over an opening 51 defined on one side of the water chamber 20 and receive therethrough at least one reactant capable of generating gas by at least one chemical reaction. In the exemplary embodiment shown in FIG. 2A, the reactant inlet 52 is movably coupled over the opening 51 of the water chamber 20 to move between an open position and a closed position about a pivot so that the water chamber 20 receives the reactant when the reactant inlet 52 is in its open position and that an interior of the water chamber 20 is isolated from atmosphere when such an inlet 52 is in its closed position. Therefore, as the reactant is fed to the water chamber 20 and generates the gas therein, the water chamber 20 may be able to maintain its pressure which is to increase as the chemical reaction precedes and to develop the foregoing pressure difference. At least one conduit 22 is disposed between the water outlet 21 and the interior of the water chamber 20 where the water outlet 21 is arranged to have a proper shape and/or size in order to dispense water therethrough at a desirable speed and/or flow rate. In addition, the control valve 23 is disposed along the conduit 22 and/or at the water outlet 21 to control flow of water through the water outlet 21. More particularly, the trigger or switch may be operatively coupled to the control valve 23 so that the control valve 23 opens and closes to commence and stop dispensing water through the water outlet 21 on an user command, respectively. It is appreciated that the water chamber 20 is preferably arranged to be airtight except the foregoing designated inlets and outlets to prevent leakage of the gas therefrom and to maintain the pressure difference with respect to atmosphere.

The water gun 11 may optionally include an air pump 30 arranged to allow the user to manually compress air. Such an air pump 30 is generally similar to or identical to those described in conjunction with FIGS. 1A to 1C and disposed in series with the water chamber 20 so that compressed air may be delivered to the water chamber 20 through a conduit 38. In order to prevent a retrograde flow of gas from the water chamber 20 to the air pump 30, a control valve 37 such as an one-way valve may also be disposed along the conduit 38. The control valve 37 may also be arranged so that the compressed air is delivered to the water chamber 20 whenever pressure of the compressed air exceeds pressure inside the water chamber 20 or, alternatively, upon receiving the user input or signal.

In operation, an user opens the water inlet of the water chamber 20, fills the chamber 20 with water to a proper level, and closes the water inlet. The user opens the reactant inlet 52, supplies one dose of reactant to the water chamber 20, and then closes the reactant inlet 52, thereby separating or isolating the water chamber 20 from atmosphere. When the reactant undergoes the chemical reaction and begins to generate gas in the water chamber 20 (i.e., the water chamber 20 serving as the gas-generation chamber), the pressure inside the water chamber 20 also begins to increase and pressure difference is being developed between the interior of the water chamber 20 and the atmosphere (i.e., the water chamber 20 serving as the pressure-driving chamber). As the user presses, squeezes or otherwise activates the trigger, the control valve 23 opens and water begins to be dispensed from the water chamber 20 by the pressure gradient or difference developed between the water chamber 20 and atmosphere. As water is dispensed from the water chamber 20, the gas pressure in the water chamber 20 also begins to decrease in proportion with an amount of the dispensed water, which may render the reactant(s) remaining in the water chamber 20 undergo further chemical reaction as will be explained in greater detail below. When the user releases the trigger, the control valve 23 doses and the water gun 11 stops to dispense water. As a water level in the water chamber 20 becomes lower than a preset level, the user may refill the water chamber 20 with water. The user may also open the reactant inlet 52 and provide more reactants to the water chamber 20 to generate more gas inside the water chamber 20. When the water gun 11 includes the optional air pump 30 which is coupled to the water chamber 20 in a series configuration, the user may press the handle 31 of the air pump 30 and compress air which is trapped therein. Depending upon the pressure of the compressed air, the user can simultaneously deliver the compressed air to the water chamber 20, thereby increasing or at least maintaining the pressure inside the water chamber 20. When the air pressure from the air pump 30 is lower than the gas pressure inside the water chamber 20, the control valve 38 may remain closed to prevent retrograde flow of the gas into the air pump 30. As the user dispenses water from the water chamber 20 and as the gas pressure falls below the air pressure, the compressed air may then enter the water chamber 20 and contribute to dispensing water from the water chamber 20.

FIG. 2B is a schematic diagram of an exemplary water gun similar to that of FIG. 2A and having a separate reactant chamber for storing reactants and providing such to a water chamber to generate gas therein according to the present invention. For example, an exemplary water gun 11 of FIG. 2B is generally similar or identical to that shown in FIG. 2A, e.g., having a similar or identical water chamber 20, water outlet 21, conduit 22, control valve 23, and an optional air pump 30 including another conduit 38 and control valve 37. The water gun 11 shown in FIG. 2B, however, includes a separate reactant chamber 50 which is operatively coupled to the water chamber 20 in order to supply multiple doses of reactants to the water chamber 20. Such a reactant chamber 50 generally defines an opening 51 on one side thereof and has a reactant inlet 52 movably disposed over the opening 51 to move between an open position and a closed position in order to receive multiple doses of reactants therethrough in its open position and to isolate (or separate) an interior of reactant chamber 50 from atmosphere in its closed position. The reactant chamber 50 may form multiple retainers each of which may be arranged to retain one dose and/or a preset number of doses of solid or liquid reactants therein. In addition, the reactant chamber 50 may have a loading unit (not shown in the figure) arranged to transport one dose or a preset number of doses of solid or liquid reactants to the water chamber 20. Furthermore, such a reactant chamber 50 may include an airlock 54 along a conduit connecting the reactant chamber 50 to the water chamber 20, where the airlock 54 is arranged to operate between a closed position and an open position, to seal the water chamber 20 from atmosphere in its closed position, and to open or render the water chamber 20 in fluid communication with the reactant chamber 50 in its open position. Such an airlock 54 is useful when the reactant inlet 52 cannot provide complete isolation or separation of the reactant chamber 50 in its closed position. Similar to the embodiment of FIG. 2A, the water gun 11 may optionally include an air pump 30 and control valve 37 similar or identical to those described in conjunction with FIG. 2A.

In operation, an user opens the water inlet of the water chamber 20, fills the chamber 20 with water to a proper level, and closes the water inlet. The user opens the reactant inlet 52, supplies one dose of reactant to the reactant chamber 50, and then closes the reactant inlet 52, thereby separating or isolating the reactant chamber 50 from atmosphere. Thereafter, the loading unit of such a reactant chamber 50 transports one or a preset number of doses of reactants to the water chamber 20 either automatically or on an user command. As the reactant undergoes the chemical reaction and begins to generate gas in the water chamber 20 (i.e., the water chamber 20 also serving as the gasgeneration chamber), the pressure inside the water chamber 20 also begins to increase and pressure difference is being developed between the interior of the water chamber 20 and the atmosphere (i.e., the water chamber 20 serving as the pressure-driving chamber). As the user presses, squeezes or otherwise activates the trigger, the control valve 23 opens to dispense water from the water chamber 20 by the pressure gradient or pressure difference developed between the water chamber 20 and atmosphere. As water is dispensed from the water chamber 20, the gas pressure in the water chamber 20 begins to decrease, and the reactant remaining in the water chamber 20 may further react to generate more gas as will be explained in greater detail below. When the user releases the trigger, the control valve 23 closes and the water gun 11 stops to dispense water. As a water level in the water chamber 20 becomes lower than a preset level, the user may refill the water chamber 20 with water. In addition, as the reactants in the reactant chamber 50 are consumed, the user may also open the reactant inlet 52 and provide more reactants to the reactant chamber 50. When the water gun 11 has the optional air pump 30, the user may press the handle 31 of the air pump 30 and compress air which is trapped therein. Depending upon the pressure of the compressed air, the user can simultaneously deliver the compressed air to the water chamber 20, thereby increasing or maintaining the pressure in the water chamber 20. When the air pressure from the air pump 30 is lower than the gas pressure in the water chamber 20, the control valve 38 may remain closed to prevent retrograde flow of the gas into the air pump 30. As the user dispenses water from the water chamber 20 and the gas pressure falls below the air pressure, the compressed air may enter the water chamber 20 and dispense water from such a water chamber 20.

In another aspect of the present invention, other gas-powered water guns may be provided to dispense water through their water outlets on user commands by pressure differences developed by gas between interiors of the water guns and atmosphere. FIGS. 2C and 2D exemplify various water guns including separate water chambers and gas-generating chambers.

FIG. 2C is a schematic diagram of an exemplary water gun having a water chamber for storing water and a separate reaction chamber for receiving reactants and generating gas therein according to the present invention. An exemplary water gun 11 of FIG. 2C is generally similar to that of FIG. 2A, e.g., having a similar or identical water chamber 20, water outlet 21, conduit 22, control valve 23, and an optional air pump 30 including an additional conduit 38 and control valve 37. The water gun 11 of FIG. 2C, however, includes a separate reaction (or gas-generating) chamber 60 which is operatively in fluid communication with the water chamber 20 to supply gas thereto. For example, such a reaction chamber 60 is typically arranged to receive at least one reactant capable of generating gas by at least one chemical reaction, to initiate such a reaction of the reactant therein to generate such gas, and to provide such gas to the water chamber 20 either directly or indirectly to increase its internal pressure. The reaction chamber 60 generally defines an opening 61 on one side thereof and has a reactant inlet 62 movably disposed over the opening 61 to move between an open position and a closed position to receive one dose or a preset doses of reactants therethrough in its open position and then to isolate (or separate) an interior of reaction chamber 60 from atmosphere in its closed position to prevent loss of such gas into atmosphere. The reaction chamber 60 is coupled to the water chamber 20 through a pair of conduits 63, 64 between which a control valve 65 is disposed so as to regulate a flow of gas therethrough. The reaction chamber 60 preferably includes a safety valve 68 so as to purge the gas through a safety outlet 69 into atmosphere when pressure inside the reaction chamber 60 exceeds a preset limit. Such a reaction chamber 60 may also include a discharge valve 66 in order to discharge undesirable reaction byproducts therefrom through a discharge outlet 67, e.g., when concentration of such byproducts increase over a preset level, whenever a new dose of the reactant is provided into the reaction chamber 60, when a volume of such byproducts exceeds a preset level, and so on. The discharge valve 66 may be arranged to open and close manually so as to allow the user to discharge the reaction byproducts as well. When the water gun 11 includes an optional air pump 30 and control valve 37 similar or identical to those described in conjunction with FIG. 2A, the reaction chamber 60 is disposed in parallel with the air pump 30 with respect to the water chamber 20 such that water in the water chamber 20 may be dispensed by either or both of the gas supplied from the reaction chamber 60 and the compressed air delivered from the air pump 30.

In operation, an user opens the water inlet of the water chamber 20, fills the chamber 20 with water to a proper level, and closes the water inlet. The user opens the reactant inlet 62, supplies one dose of reactant to the reaction chamber 60, and then closes the reactant inlet 62, thereby separating (or isolating) the reaction chamber 60 from atmosphere. As the reactant begins the chemical reaction and begins to generate gas in the reaction chamber 60, the gas is delivered to the water chamber 20 at least substantially simultaneously or as the user signal or command is delivered to the control valve 65. Thereafter, pressure inside the water chamber 20 begins to increase and pressure difference is developed between the interior of the water chamber 20 and the atmosphere (i.e., the water chamber 20 serving as the pressure-driving chamber). As the user presses, squeezes or otherwise activates the trigger, the control valve 23 opens to dispense water from the water chamber 20 by the pressure gradient or difference. As the gas is delivered to the water chamber 20, the pressure in the reaction chamber 20 begins to decrease, and the reactant remaining in such a reaction chamber 20 may begin to further react to generate more gas. When the user releases the trigger, the control valve 23 closes and the water gun 11 stops to dispense water. When at least a substantial portion of the reactant in the reaction chamber 60 is consumed, the user opens the reactant inlet 62 and loads more reactants thereinto to continue generation of such gas therein. To prevent or minimize loss of the gas inside the water chamber 20, the control valve 65 may be closed during the loading of the reactants so that the water chamber 20 may be separated from the reaction chamber 60. Other operational characteristics of the gas-powered water gun of FIG. 2C is similar to those described in FIGS. 2A and 2B.

FIG. 2D is a schematic diagram of an exemplary water gun similar to that of FIG. 2C and having a separate reactant chamber for storing reactants and supplying such to the reaction chamber so as to generate gas therein according to the present invention. An exemplary water gun 11 of FIG. 2D is somewhat similar to that shown in FIG. 2B, e.g., including an identical water chamber 20, water outlet 21, conduit 22, control valve 23, and an optional air pump 30 with another conduit 38 and control valve 37. The water gun 11 of FIG. 2D, however, includes a separate reaction (or gas-generating) chamber 60 which is operatively disposed between the water chamber 20 and the reactant chamber 50. Such a reaction chamber 60 is typically arranged to receive from the reactant chamber 50 one dose and/or a preset doses of at least one reactant capable of generating gas by at least one chemical reaction, to initiate such a reaction of the reactant therein to generate such gas, and then to provide the gas to the water chamber 20 directly or indirectly to increase its internal pressure. The reaction chamber 60 is coupled to the water chamber 20 through a pair of conduits 63, 64 between which a control valve 65 is disposed so as to regulate a flow of gas therethrough. The reaction chamber 60 includes a safety valve 68 and discharge valve 66 which are generally similar to those of FIG. 2C. When the water gun 11 includes an optional air pump 30 and control valve 37 similar to those described in conjunction with FIGS. 2A to 2C, the reaction chamber 60 may be disposed in parallel with the air pump 30 with respect to the water chamber 20 such that water in the water chamber 20 may be dispensed by either or both of the gas supplied from the reaction chamber 60 and compressed air delivered from the air pump 30. An optional airlock 54 may further be disposed along a conduit between the reactant chamber 50 and water chamber 20 and arranged to operate between a closed position and an open position such that the airlock 54 isolates the water and reaction chambers 20, 60 from atmosphere in its closed position, and opens or renders the reaction chamber 60 in fluid communication with the reactant chamber 50 in its open position. Such an airlock 54 is useful when the reactant chamber 50 cannot provide complete isolation or separation of the reactant chamber 50 in its closed position. Similar to the embodiments of FIGS. 2A to 2C, the water gun 11 may optionally include an air pump 30, where the reaction chamber 60 and the air pump 30 are connected in a parallel arrangement with respect to the water chamber 20 to provide the reaction-generated gas and the compressed air to the water chamber 20, respectively.

In operation, an user opens the water inlet of the water chamber 20, fills the chamber 20 with water to a proper level, and closes the water inlet. The user opens the reactant inlet 52, supplies (or loads) reactants into the reactant chamber 50, and closes the reactant inlet 52, thereby separating the reactant chamber 50 from atmosphere. A loading unit of the reactant chamber 50 then transports one dose and/or a preset doses of reactants into the reaction chamber 60 automatically and/or on the user signal. As the reactant begins to react, generates gas in the reaction chamber 20 (i.e., the reaction chamber 60 is the gas-generation chamber), and delivers the gas to the water chamber 20, pressure inside the water chamber 20 begins to increase and pressure difference begins to develop between the interior of the water chamber 20 and the atmosphere (i.e., the water chamber 20 is the pressure-driving chamber). When the user presses, squeezes or otherwise activates the trigger, the control valve 23 opens to dispense water from the water chamber 20 by the pressure gradient or pressure difference developed between the water chamber 20 and atmosphere. As water is dispensed from the water chamber 20, the gas pressure inside the water chamber 20 begins to decrease, and such reactants remaining in the water chamber 20 may react to generate more gas as will be explained in greater detail below. When the user releases the trigger, the control valve 23 closes and the water gun 11 stops dispensing water. When a water level in the water chamber 20 becomes lower than a preset level, the user may refill the water chamber 20 with water. In addition, as the reactants in the reactant chamber 50 are consumed, the user opens the reactant inlet 52 and provides more reactants to the reactant chamber 50. When the water gun 11 has the optional air pump 30, the user may press the handle 31 of the air pump 30 and compress air trapped therein. Depending upon the pressure of the compressed air, the user can simultaneously deliver the compressed air to the water chamber 20, thereby increasing or maintaining the pressure in the water chamber 20. When the air pressure from the air pump 30 becomes lower than the gas pressure in the water chamber 20, the control valve 38 may remain dosed to prevent retrograde flow of the gas into the air pump 30. As the user dispenses water from the water chamber 20 and the gas pressure falls below the air pressure, the compressed air may enter the water chamber 20 and dispense water from such a water chamber 20.

In another aspect of the present invention, gas-powered water guns may further be provided to dispense water through their water outlets on user commands through pressure difference which is developed by gas between interiors of the water guns and atmosphere and also to store such gas in gas storage chambers. FIGS. 3A and 3B exemplify various water guns which include separate gas chambers which may be provided in various arrangements.

FIG. 3A is a schematic diagram of an exemplary water gun with a water chamber for receiving reactants and generating gas therein and a separate gas chamber for storing the gas according to the present invention. An exemplary water gun 11 shown in FIG. 3A is generally similar to that of FIG. 2A, e.g., including a water chamber 20 which also serves as a gas-generating chamber and a pressure-driving chamber, a water outlet 21, a conduit 22 connecting the water chamber 20 to the water outlet 21, a control valve 23 operatively coupled to a trigger, and an optional air pump 30 which has its own conduit 38 and control valve 37. The water gun 11 shown in FIG. 3A further includes a separate gas chamber 70 disposed between the water chamber 20 and the air pump 30. More particularly, as the reactant is fed to the water chamber 20, undergoes the chemical reaction, and generates gas therein, such a gas chamber 60 is arranged to receive at least a portion of the gas from the water chamber 20 and to store the gas therein when pressure inside the water chamber 20 exceeds pressure inside the gas chamber 70. When the pressure of the water chamber 20 decreases as the water is dispensed from the water gun below the pressure inside the gas chamber 70, the gas stored in the gas chamber 70 is delivered into the water chamber 20, thereby increasing the pressure inside the water chamber 20 and further dispensing water therefrom through the water outlet 21. The user may also compress air by the air pump 30 and supply the compressed air to the gas chamber 70 which then delivers such to the water chamber 20 to dispense water therefrom.

FIG. 3B is a schematic diagram of an exemplary water gun having a water chamber for storing water and a separate gas chamber for receiving reactants, generating gas therein, and storing such gas therein according to the present invention. An exemplary water gun 11 of FIG. 3B is similar to that shown in FIG. 3A, except that a reactant inlet 52 is provided not in the water chamber 20 but rather in the gas chamber 70. Therefore, according to this embodiment, the gas chamber 70 serves as a gas-generating chamber, while the water-chamber operates as a pressure-driving chamber. For example, as the reactant is supplied to the gas chamber 70 through its reactant inlet 52, undergoes the chemical reaction, and generates gas therein, the gas chamber 70 delivers such gas to the water chamber 20 when pressure inside the gas chamber 70 exceeds pressure inside the water chamber 70. When the pressure inside the gas chamber 70 is lower than that inside the water chamber 20, however, such a gas chamber 70 simply stores the gas therein until its pressure exceeds that of the water chamber 20 or until it receives an user input or command.

In another aspect of the present invention, gas-powered water guns may be provided so as to dispense water through their water outlets on user commands by pressure difference developed by gas between interiors of the water guns and atmosphere by storing the gas in gas storage chambers and storing reactants in reactant chambers. FIGS. 3C and 3D exemplify various water guns including separate gas chambers and reactant chambers having various configurations.

FIG. 3C is a schematic diagram of an exemplary water gun similar to that of FIG. 3A and having a separate reactant chamber to store reactants and to supply such reactants to the water chamber in order to generate gas therein according to the present invention. An exemplary water gun 11 of FIG. 3C is similar to that of FIG. 3A, except that such a water gun 11 includes a separate reactant chamber 50 defining an opening 51 and having a movable reactant inlet 52 arranged similar to those described in conjunction with FIGS. 2B and 2D. Accordingly, after the user loads multiple doses of reactants into the reactant chamber 50, the aforementioned loading unit of the reactant chamber 50 transports each dose and/or a preset number of doses of reactants to the gas-generating and pressure-driving water chamber 20 automatically or upon receiving the user signal or command. Similar to that of FIG. 3A, the gas chamber 70 may store at least a portion of the gas generated through the chemical reaction in the water chamber 20 or to deliver the gas stored therein and/or compressed air supplied by the air pump 30 to the water chamber 20.

FIG. 3D is a schematic diagram of an exemplary water gun similar to that of FIG. 3B and having a separate reactant chamber for storing reactants and supplying such to the gas chamber in order to generate gas therein according to the present invention. Such a water gun 11 exemplified in FIG. 3D is similar to that of FIG. 3B, except that such a water gun 11 includes a separate reactant chamber 50 identical to that of FIG. 3C. Therefore, as the user loads multiple doses of reactants into the reactant chamber 50, the aforementioned loading unit of the reactant chamber 50 transports each dose and/or a preset number of doses of reactants to the gas-generating gas chamber 70. The gas generated by the reactant inside such a gas chamber 70 may then be supplied to a pressure-driving water chamber 20 automatically and/or upon receiving the user signal or command. Similar to that of FIG. 3B, the gas chamber 70 stores at least a portion of the gas generated through the chemical reaction in the water chamber 20 or delivers such gas stored therein and/or compressed air supplied by the air pump 30 to the water chamber 20.

In another aspect of the present invention, gas-powered water guns may be provided so as to dispense water through their water outlets on user commands by pressure difference developed by gas between interiors of the water guns and atmosphere by generating gas in reaction chambers, by storing such gas in gas storage chambers, and by storing reactants in reactant chambers. FIGS. 3E and 3F exemplify various water guns with separate reaction chambers, gas chambers, and reactant chambers having various configurations.

FIG. 3E is a schematic diagram of an exemplary water gun having a water chamber for storing water, a separate reaction chamber for receiving reactants and generating gas as well as a separate gas chamber for storing gas therein according to the present invention. An exemplary water gun 11 of FIG. 3E is similar to those of FIGS. 3A and 3B, except that such a water gun 11 includes a separate reaction chamber 60 defining an opening 61 and having a movable reactant inlet 62 arranged similar to that described in conjunction with FIG. 2C. When the user loads one dose and/or a preset number of doses of reactants into the gas-generating reaction chamber 60, the reactant undergoes the chemical reaction and generates gas thereby. As shown in the figure, the reaction chamber 60 may indirectly supply the gas to the pressure-driving water chamber 20 via the gas chamber 70. In this embodiment, the gas chamber 70 receives all the gas generated in the reaction chamber 60 and delivers the gas to the water chamber 20 depending upon their pressures either automatically or upon receiving the user signal or command. Accordingly, such a gas chamber 70 serves as an additional storage chamber of such gas. In another embodiment which is not shown in the figure, an additional conduit is disposed between the water chamber 20 and the reaction chamber 60 such that the reaction chamber 60 may deliver such gas directly to the water chamber 20 or indirectly thereto through the gas chamber 70. In addition, the gas chamber 70 may further be arranged to receive compressed air from the air pump 30 and deliver such to the water chamber 20.

FIG. 3F is a schematic diagram of an exemplary water gun similar to that of FIG. 3E and having a separate reactant chamber for storing reactants and supplying such to the reaction chamber so as to generate gas therein according to the present invention. An exemplary water gun 11 of FIG. 3F is similar to that of FIG. 2D (or FIG. 3D), except that the water gun 11 of FIG. 3F includes a separate gas chamber 70 (or reaction chamber 60). More particularly, the gas-generating reaction chamber 60 may be disposed between the reactant chamber 50 and gas chamber 70 which may be in turn disposed in an upstream of the pressure-driving water chamber 20. Thus, when the user loads multiple doses of reactants into the reactant chamber 50, a loading unit thereof may transport one dose and/or a preset number of doses of reactants into the gas-generating reaction chamber 60. The reactant undergoes the chemical reaction in the reaction chamber 60 and generates gas therein. Similar to that of FIG. 3E, such a reaction chamber 60 may indirectly supply all or at least a portion of such gas to the pressure-driving water chamber 20 through the gas chamber 70 either automatically or upon receiving the user signal or command. In the alternative and when an additional conduit is provided between the reaction chamber 60 and water chamber 20, the reaction chamber 60 may deliver a portion of the gas directly to the water chamber 20 or indirectly thereto through the gas chamber 70. The gas chamber 70 may additionally be arranged to receive compressed air from the air pump 30 and deliver such to the water chamber 20 automatically or upon receiving the user signal or command.

Configurational and/or operational variations and/or modifications of such foregoing exemplary embodiments of FIGS. 2A to 2D and FIGS. 3A to 3F (referred to as FIGS. 2A to 3F hereinafter) also fall within the scope of the present invention. More particularly, various chambers, various units thereof, various control valves, various conduits, and parallel and/or series arrangements therebetween may be modified and/or varied, and additional chambers, valves, and conduits may be incorporated without departing from the scope of the present invention.

Various water chambers described in FIGS. 2A to 3F may be made of various materials and/or in various configurations. For example, such a water chamber may be made of any material such as, e.g., plastics or composites, as long as it does not leak water therethrough (i.e., water-resistant) and as long as it endures gas pressure. The water chamber may also be constructed in any configuration as long as it may receive and store a preset amount of water therein (i.e., watertight) except through designated inlets and/or outlets. The water chamber may be arranged to have any shape and/or size, and disposed in any location of the water gun as far as it does not hinder or obstruct any operation of other chambers of the water gun. In addition, multiple water chambers may be incorporated into such a water gun in a series and/or parallel configuration so as to increase a storage capacity of the water gun and to provide multiple water supply routes. When such a water chamber is used only for storing water therein, it may be made similar to those of conventional water guns. However, when the water chamber is used as the gas-generating and/or pressure-driving chamber, such a water chamber may preferably be made of more durable materials and/or in more resilient configurations.

Such a water chamber may include a variety of conduits delivering the gas or water thereto or therefrom and/or a variety of valves therealong. For example, the water chamber may be arranged to be in fluid communication with various gas-generating chambers through a variety of conduits in order to receive the gas therethrough, and in fluid communication with various pressure-driving chambers to supply water thereto. Depending upon detailed configurations, such conduits may connect the water chamber to the gas-generating chamber, pressure-driving chamber, optional manual air pump, and/or other chambers either indirectly or directly in a parallel or series arrangement. Furthermore, when the reactant requires water as a medium or a reacting compound of the gas-generating chemical reaction, the water chamber may be connected to the gas-generating chamber to supply water thereto. Such a water chamber may include at least one safety valve so as to prevent over-pressurizing thereof by the gas. In addition, such a safety valve may be used to dispense water under a preset pressure to minimize possible body injury of a person subjected to water dispensed by the gas-powered water gun of this invention.

The above water outlets of FIGS. 2A to 3F may also be arranged to dispense water in various configurations. Similar to conventional water guns, the foregoing water outlet may be arranged to be always open to atmosphere and to dispense water whenever the pressure inside the water chamber exceeds atmospheric pressure. In such an embodiment, the water gun may include a separate gas-generating chamber arranged to supply the gas to the water chamber on the user signal or command and to be otherwise closed to the water chamber to prevent loss of the gas therefrom. Alternatively, the water outlet may be operatively coupled to the trigger, arranged to open to atmosphere in order to dispense water therefrom only upon receiving the user signal or command, and otherwise closed to atmosphere. Depending upon user's selection or command, such a water outlet may also be arranged to dispense water as a continuous stream, a series of water pulses, a burst of water, a tubular jet, a spray, and so on. Multiple water outlets may also be incorporated so that water may be dispensed in a variety of configurations depending upon, e.g., gas pressure, force applied to the trigger, a number of such outlets recruited for dispensing water, and so on. A manual or automatic distance selector or sensor may also be incorporated in order to focus multiple streams of water in different distances. In addition, the water outlet may be arranged to adjust its opening area so that a linear velocity and/or a flow rate of dispensed water may be adjusted manually or automatically based on, e.g., gas pressure, an amount of water stored in the water chamber, and the like.

Reaction chambers described in FIGS. 2A through 3F may be made of various materials and/or in various configurations. Therefore, the reaction chamber may be made of any suitable material such as, e.g., plastics, metals or composites, as far as it is chemically inert and/or resistant to the reactant, its reaction intermediates and/or byproducts and as long as it endures pressure of the gas generated therein. The reaction chamber may also be constructed in any configuration as long as it may receive the reactant, store the gas generated thereby, and then maintain the pressure of the gas (i.e., airtight) except through designated inlets and/or outlets. The reaction chamber may also be arranged to have any shape and/or size, and disposed in any location of the water gun as far as it does not hinder any operation of other chambers of the water gun. For safety reasons, however, the reaction chamber is preferably disposed inside the water gun in order to minimize injuries in case of explosion thereof. In addition, multiple reaction chambers may be incorporated into the water gun in a series and/or parallel configuration in order to increase a gas-generating capacity of the water gun and to provide multiple gas supply routes. Such a reaction chamber may be used only for generating gas therein or used as the gas-generating and pressure-driving chamber as well.

The reaction chamber may include a variety of conduits delivering the gas or water thereto or therefrom and/or a variety of valves therealong. For example, the reaction chamber may be arranged to be in fluid communication with various pressure-driving chambers through various conduits in order to deliver the gas therethrough and in fluid communication with various gas storage chambers to store such gas therein. Depending upon detailed configurations, various conduits may connect the reaction chamber to the water chamber or other pressure-driving chamber, optional manual air pump, and the like either indirectly or directly in a parallel and/or series arrangement. Furthermore, when the reaction may require water as a medium for the reactant or as a reacting compound, the reaction chamber may include a separate water inlet arranged to receive water therethrough from an external source. In the alternative, the reaction chamber may be connected to the water chamber to receive water therefrom. In this embodiment, the user may manually supply a desirable amount of water to the reaction chamber whenever deemed necessary. Alternatively, the reaction chamber may be operatively coupled to the water chamber and/or other chambers of the water gun such that a preset amount of water may be provided into the reaction chamber, e.g., whenever a new dose of reactant may be delivered into the reaction chamber, as the gas pressure inside the reaction chamber falls below a preset value, when a preset amount of water is dispensed from the water chamber, and so on. In particular, the reactant loading unit may be coupled to the water inlet of the reaction chamber or a water loading unit therefor so that the water loading unit receives water from the water chamber whenever the reactant loading unit transports a preset dose of reactant to the reaction chamber.

As discussed above, the reaction chamber may also include the discharge valve to discharge the undesirable reaction byproducts therefrom. Similar to the foregoing water inlet, the user may open the discharge valve to discharge a desirable amount of the byproducts or reaction mixture whenever deemed necessary. In the alternative, the reaction chamber may be operatively coupled to the water chamber and/or other chambers of the water gun so that a preset amount of byproducts or such an amount of the reaction mixture may be discharged from the reaction chamber, e.g., whenever a new dose of reactant may be delivered into the reaction chamber, as the gas pressure inside the reaction chamber falls below a preset value, whenever a preset amount of water is dispensed from the water chamber, when temperature inside the reaction chamber deviates from a desirable range, and the like. The reactant loading unit may be similarly coupled to the discharge valve of the reaction chamber or a discharge unit of the reaction chamber so that the discharge valve or unit discharges a preset amount of the byproducts and/or reaction mixture out of the reaction chamber whenever the reactant loading unit transports a preset dose of reactant to the reaction chamber. In one embodiment, the byproducts and/or reaction mixture may be discharged through the discharge valve directly out of the water gun. In another embodiment, the water gun includes a separate collection chamber in which the byproducts or reaction mixture may be collected and disposed thereafter. In another alternative, such byproducts or reaction mixture may be discharged from the reaction chamber and then transported into the water chamber to be discharged out of the water gun along with water dispensed through the water outlet. It is appreciated, in this embodiment, that the byproducts or reaction mixture is preferably nontoxic or does not initiate any undesirable chemical reaction or dissolution when they are mixed with water in the water chamber. In addition, at least one filter is disposed in an upstream of the water outlet so as to prevent any precipitation of the reactant and/or byproduct from clogging the water outlet.

The reaction chamber may be arranged to regulate a temperature and/or a pressure therein as well. Such embodiments are particularly useful when rates or extents of the gas-generating reaction may be controlled by such a temperature and/or pressure. For example, various products obtained by the reaction such as the gas and byproducts almost always have a greater volume than the reactants and, accordingly, an increase in the pressure inside the reaction chamber may reduce progression of the reaction. More particularly, when the gas-generating reaction is a reversible reaction, an increase in the pressure generally favors a backward reaction than a forward reaction, thereby decreasing an extent and/or yield of the reaction and possibly reducing a volume of the gas in the reaction chamber. In such a case, the reaction chamber may be arranged to transport at least a portion of the gas to the gas chamber and/or water chamber, thereby reducing its pressure and increasing the amount of gas present inside the water gun. When the gas-generating reaction is exothermic, the temperature inside the reaction chamber will tend to increase as the reaction proceeds and the gas is generated. When such a reaction is a reversible one, such an increase in pressure will decrease the extent and/or yield of the reaction. Accordingly, the reaction chamber may be arranged to be cooled using the air and/or by circulating the water stored in the water chamber.

Such a reaction chamber may be arranged to include at least one gas outlet valve which may be regulated by various modes. In one embodiment, such a control valve may be manually controlled by the user so that he or she can accumulate the gas in the reaction chamber and then deliver such gas to the gas chamber and/or pressure-driving chamber whenever needed. In another embodiment, the control valve may be regulated based on the pressure of the reaction chamber, pressure-driving chamber, water chamber, air pump, and so on. This embodiment offers the benefit of maintaining the pressure inside the pressure-driving chamber at a relatively constant level. In another embodiment, the control valve may be regulated based on the flow of the gas from the reaction chamber to another chamber as well.

The reaction chamber may also be arranged to include therein one or more sub-chambers for various purposes. For example, such sub-chambers may operate as separate reaction chambers so that they may generate the gas sequentially or together. Such sub-chambers may also be arranged to control its temperature and/or pressure individually, thereby attaining different reaction extents and/or yields therein. The sub-chamber may also serve as a reactant storage which stores multiple doses of the reactants, while keeping them from initiating the gas-generating reaction by preventing them from contacting the air, water, gas, other reactants, reaction byproducts, and the like. In addition, the sub-chamber may be arranged to have an airlock mechanism so that the gas and/or air does not get out of or into the reaction chamber while loading the reactants into the reaction chamber.

Gas chambers described in FIGS. 3A to 3F may be made of various materials and/or in various configurations. For example, such a gas chamber may be made of any suitable material such as, e.g., plastics, metals or composites, as far as it is chemically inert and/or resistant to the gas and as far as it endures the gas pressure. The gas chamber may also be provided in any configuration as long as it may receive the gas from the gas-generating chamber, store the gas, and maintain the gas pressure (i.e., airtight) except through designated inlets and/or outlets. In addition, the elastic gas chamber may be made of any conventional elastic material and/or may be arranged to have any conventional elastic configuration. The gas chamber may also be arranged to have any shape and/or size and disposed in any location of the water gun as long as it does not hinder any operation of other chambers of such a water gun. For safety reasons, however, the gas chamber may be disposed inside the water gun to minimize injuries in case of explosion thereof. In addition, multiple gas chambers may be incorporated in a series and/or parallel configuration in order to increase a gas-storing capacity of the water gun or to provide multiple gas supply routes. Such a gas chamber may be used only for storing gas therein or as the gas-generating and pressure-driving chamber as well.

The gas chamber may include a variety of conduits for delivering the gas thereto or therefrom and various valves therealong. Through these conduits and valves, the gas chamber may be coupled to other chambers of the water gun in a series and/or parallel arrangement. For example, such a gas chamber may be disposed between the water chamber and reaction chamber, between the reaction chamber and optional air pump, in a downstream of the water and reaction chambers, and the like. In any of these embodiments, the gas chamber may be controlled manually by the user or automatically. Similar to the foregoing reaction chamber, various pressure- and/or volume-regulating control valves may be incorporated to regulate, e.g., the pressure inside the gas chamber, the flow of the gas into or out of the gas chamber, and so on. When desirable, the reaction chamber may be arranged to deliver the gas either to the gas chamber or to the pressure-driving chamber such that the gas chamber may not be able to receive all the gas generated in the reaction chamber.

Reactant chambers described in FIGS. 2A through 3F may be made of various materials and/or in various configurations. For example, the reactant chamber may be made of any materials such as, e.g., plastics, metals or composites, as far as it is chemically inert and resistant to the reactant. Such a reactant chamber may be provided in any configuration as long as it may receive multiple doses of reactants from the user, store the reactants, and deliver a preset amount of the reactants to the gas-generating chamber either manually or automatically. The reactant chamber may be arranged to have any shape and/or size and disposed in any location of the water gun as far as it does not hinder any operation of other chambers of such a water gun. Multiple reactant chambers may be incorporated in a series and/or parallel configuration in order to increase a storing capacity of the reactant and/or to provide multiple supply routes of the same or different reactants. When desirable, the above reactant chambers may be arranged to isolate the stored reactant from water, air or the reactants undergoing the chemical reaction in the gas-generating chamber.

Such a reactant chamber may include a variety of conventional loading units. First, the loading unit may be manipulated manually by the user to load one or a preset number of doses of reactants to the gas-generating chamber. Such a loading unit may include a handle and/or a lever to transport the preset amount of the solid or powder reactant or may include a syringe or spoid to transport such an amount of the liquid reactant. Second, the loading unit may be operatively coupled to other chambers of the water gun such as, e.g., the water chamber, gas-generating chamber, gas chamber, pressure-driving chamber, and the like, such that preset events occurring in such a chamber may activate such a reactant chamber to transport one or preset number of doses of reactants into the gas-generating chamber. Examples of such events may include, but not be limited to, a decrease in the gas pressure in the gas-generating chamber due to consumption of the reactants, a decrease in the water level in the water chamber after dispensing water, an accumulation of the reaction wastes or byproducts in the gas-generating chamber, dispensing of such waste or byproducts, and the like. In general, such a loading unit is arranged to convey or pressure-feed one or a preset number of the solid reactants, to convey or drip a preset volume or weight of the powder or liquid reactant, or to transport the solid, powder or liquid reactant using other conventional solid, powder, and liquid transporting mechanisms. When the reactant chamber receives multiple reactants, the loading unit may be arranged to transport such reactants in a preset ratio so as to satisfy the reaction stoichiometry. The loading unit may also be arranged to include conventional recoil mechanisms for repeated use. Thus, an exemplary loading unit may include a spring which recoils to its unstressed position after loading one or a preset number of doses of reactants into the gas-generating chamber.

In another aspect of the present invention, various reactants may be provided to generate gas by at least one chemical reaction thereof. More particularly, such reactants are preferably engineered to be shaped, sized, and/or contained such that they may be used for the aforementioned water guns for dispensing water through a water outlet by pressure difference developed by such gas between interiors of such water guns and atmosphere. In general, such a reactant may be provided as, e.g., a solid article, a powder, and a liquid including a liquid reactant and solution thereof. The solid reactants may have a variety of shapes examples of which may include, but not be limited to, rounded or curved articles (e.g., spheres, beads, and otherwise oblong pills), pellets having circular, oval or other cross-sectional shapes, and the like. The powder reactants may be provided in various particle shapes and sizes, and may consist of particles with similar or different sizes. The powder reactants may also be granulated or loosely aggregated to facilitate transportation or handling thereof. It is to be appreciated, however, that detailed shapes and/or sizes of such solid article reactants and powder reactants are generally not material to the scope of the present invention as long as they may be easily introduced to the foregoing gas-generating chamber and/or reactant chamber and as long as they may relatively readily react to generate such gas in the gas-generating chamber. The reactants in their liquid phase may be homogeneous compounds or solutions of such reactants which are dissolved in appropriate solvents.

The foregoing solid, powder, and/or liquid reactants may also be arranged to react at a preset range of reaction rates. For example, such a reactant may consist of small particles each of which is encapsulated by other materials (i.e., microencapsulation) which may decompose in the air (or in the presence of other gases including the gas generated by the reactant) and/or dissolve in a solvent or a solution including the reactant at a controlled rate. Therefore, the reactant may be exposed to the air or to each other at a certain rate, thereby also generating the gas at a controlled rate. Such reactants engineered by the above microencapsulation techniques may also be contained in various containers or capsules and/or segmented by the dividers which may also be arranged to decompose or dissolve at certain rates. By incorporating such microencapsulation techniques, containers, capsules, and/or dividers, not only the rate of the chemical reaction of the reactants may be controlled, but also a timing (or delaying) of an initiation of such a reaction in the gas-generating chamber may be adjusted so that such a reaction may be delayed by a certain period after such reactants are transported into the gas-generating chamber. Such self-decomposing and/or self-dissolving containers and/or capsules may also be arranged to contain other solid reactants, powder reactants, and/or liquid reactants which are not prepared by the microencapsulation techniques. The foregoing techniques, containers, capsules, and/or dividers may also be utilized to stabilize the reactants, e.g., by preventing such reactants from being exposed to the air, other gases including the gas generated through the chemical reaction of the reactant, water, liquid reactants, solvents, and solutions including the reactants, by decomposing at a certain rate to expose the reactant to such, and the like.

Regardless of its shape, size, and/or phase, the reactant may consist of only a single reactive compound or may include multiple reactive compounds. In the alternative, multiple reactive compounds may be provided as separate reactants which may generate the gas when disposed together in the gas-generating chamber. When desirable, the reactant may be arranged to include one or more non-reactive compounds therein in order to enhance chemical stability and/or mechanical stability thereof. For example, the reactant may include one or more inert compounds which are distributed among the reactive compound molecules so as to prevent the reactive molecules from contacting each other and initiating the chemical reaction therebetween. Such inert compounds may also be included to improve aggregative properties of the compounds for forming such reactants into, e.g., pellets, beads, and/or other desirable shapes.

FIGS. 4A to 4C show exemplary reactant pellets having multiple reactant compounds arranged in vertical or longitudinal configurations. For example, FIG. 4A represents a schematic diagram of an exemplary gas-generating reactant pellet with two longitudinally arranged reactants or layers thereof, whereas FIG. 4B represents a schematic diagram of another exemplary gas-generating reactant pellet which has three longitudinally arranged reactants or layers thereof according to the present invention. Each of such exemplary reactant pellets 80 of FIGS. 4A and 4B are typically arranged to have a shape of a cylinder consisting of two or three layers 81A, 81B, 81C vertically disposed along its center axis, where each layer 81A, 81B, 81C is arranged to include a different reactive compound. Alternatively, each of such layers 81A, 81B, 81C may be arranged to include the same reactive compound but have different reactivity and/or solubility in a proper medium such that the reactants in different layers may not react at the same time and may not generate the gas simultaneously. This embodiment offers the benefits of avoiding a sudden surge of pressure in the gas-generating chamber as well as prolonging a period of gas generation. FIG. 4C is a schematic diagram of an exemplary gas-generating reactant pellet which includes two longitudinally arranged reactants (or layers) as well as an interlayer divider placed therebetween according to the present invention. Contrary to the exemplary embodiments of FIGS. 4A and 4B, a reactant pellet 80 of FIG. 4C includes an internal divider 82 which is typically made of an inert material arranged to be disposed between different layers 81A, 81B in order to segregate the different reactive compounds of such layers 81A, 81 b and to prevent such reactive compounds from contacting each other. It is preferred that the divider 82 be made of material soluble in a reaction medium so that the dissolved divider materials are dispensed out of the water gun with water through the water outlet. Otherwise, the gas-generating chamber may be provided with the aforementioned discharge outlet through which the divider materials may be dispensed.

FIGS. 4D to 4F show exemplary reactant pellets having multiple reactant compounds arranged in horizontal and/or radial configurations. Thus, FIG. 4D is a schematic diagram of an exemplary gas-generating reactant pellet which includes two radially arranged reactants or layers thereof, whereas FIG. 4E is a schematic diagram of an exemplary gas-generating reactant pellet including three radially arranged reactants (or layers) according to the present invention. Each of such exemplary reactant pellets 80 of FIGS. 4D and 4E are typically arranged to have a shape of a cylinder consisting of two or three layers 81A, 81B, 81C horizontally or radially disposed about its center axis, and each layer 81A, 81B, 81C is arranged to consist of a different reactive compound. Alternatively, each of such layers 81A, 81B, 81C may be arranged to include the same reactive compound but with different reactivity or solubility in a proper medium such that the reactants in different layers may not react at the same time and may not generate the gas simultaneously. Such an embodiment offers the benefits of avoiding a sudden surge of pressure in the gas-generating chamber and prolonging a period of gas generation. FIG. 4F is a schematic diagram of an exemplary gas-generating reactant pellet including two radially arranged reactants (or layers) and an interlayer divider placed therebetween according to the present invention. Contrary to the exemplary embodiments of FIGS. 4D and 4E, a reactant pellet 80 of FIG. 4F includes an internal divider 82 which is typically made of an inert material and arranged to be disposed between different layers 81A, 81B in order to segregate different reactive compounds and to prevent the reactive compounds from contacting each other. As described above, such a divider 82 is made of material soluble in a reaction medium or the gas-generating chamber is provided with the foregoing discharge outlet through which the divider materials may be dispensed.

When the reactant compounds are selected so that dissolution of the solid or powder reactant in a reaction medium or a liquid reactant is a rate-limiting step, solubility of the solid or powder reactant may be manipulated to adjust a gas-generating period of each dose of such reactants. For example, such solid or powder reactants may be enclosed in a soluble or decomposable container or capsule so that dissolution or decomposition of the container or capsule may determine a timing of an initiation of the gas-generating reaction. Alternatively, such solid or powder reactants may be engineered by the foregoing microencapsulation techniques to have a preset dissolution and/or decomposition rates. In the alternative and when the gas-generating reaction requires multiple reactive compounds, one of the reactive compounds may be supplied in a controlled amount than the other compounds such that a concentration of the controlled compound may determine the rate and/or extent of the reaction. Such an embodiment applies not only to the solid or powder reactants but also to the liquid reactants. It is to be appreciated that the embodiments described in this paragraph apply to other reactants arranged to generate the gas when exposed to the air or moist thereof and/or when multiple reactive compounds contact each other.

In contrary, some reactants may exhibit only limited solubilities in the reaction medium or a liquid reactant. It is then preferred that such a solid or powder reactant be arranged to facilitate dissolution thereof. One way of achieving such a goal is to increase a surface area of such a solid or powder reactant, e.g., by providing protrusions and/or indentations on surfaces of such reactants, by forming apertures in or through such reactants, by arranging such reactants to have porous structures, and the like. FIGS. 4G and 4H exemplify solid reactants having apertures therethrough. For example, FIG. 4G describes a schematic diagram of an exemplary gas-generating reactant pellet which is similar to those of FIGS. 4A to 4C and defines a center aperture, and FIG. 4H shows a schematic diagram of an exemplary gas-generating reactant pellet which is similar to those of FIGS. 4D to 4F and also defines a center aperture according to the present invention. Although exemplary apertures 83 are provided in center portions of pellets 80, such apertures may be provided in various arrangements. For example, apertures may be provided off-center, and multiple apertures may be formed parallel or perpendicular to each other in any region of the pellets 80. Such apertures may be formed through the pellets 80 or may be formed at certain depths but not through the pellets 80.

Regardless of their shapes and/or sizes, the above solid, powder, and/or liquid reactants may be contained or enclosed in various containers or capsules. In the alternative, the reactants may also be coated with external coating layers which may be disposed to enclose the entire portion thereof or only selected portions thereof. When desirable, non-reactive materials may be includes inside such a reactant to divide the reactant into multiple segments. FIGS. 4I and 4J show exemplary reactant pellets including exterior coated layers provided in various arrangements. For example, FIG. 4I is a schematic diagram of an exemplary reactant pellet similar to those of FIGS. 4A to 4C and 4G including an exterior coated layer, whereas FIG. 4J is a schematic diagram of an exemplary reactant pellet similar to those of FIGS. 4D to 4F and 4H and including an exterior coated layer according to the present invention. In both embodiments, external coated layers 84 are arranged to cover top portions, bottom portions, and sides of the reactant pellets 80 such that layers 81A, 81B of reactive compounds are not exposed to external environments. Once such pellets 80 are transported into the gas-generating chamber 60 of the water gun 11, the external coated layers 84 may be decomposed or dissolved, thereby exposing the layers 81A, 81B of reactants. Although not shown in the figure, such a coated layer may also be disposed to cover or enclose only a portion of the solid, powder or liquid reactant. In addition, such a coated layer may be disposed inside the solid pellet to protect a covered portion of the reactant from the external environment or to delay the initiation of the chemical reaction of the covered portion of the reactant, thereby adjusting rates of the gas-generating chemical reaction.

The foregoing reactants may be arranged to undergo the gas-generating chemical reaction by various arrangements. For example, when a single reactive compound is involved in such a chemical reaction, the reactant may be arranged to react when exposed to a proper medium such as, e.g., the air, water or other media. The reactant may also be arranged to react by shaking or otherwise mixing such, thereby increasing contact areas between the reactive molecules, removing the exterior coated layers and/or internal dividers of the reactant, and so on. The reactant may also be arranged to react when it is subjected to a pressure and/or temperature which exceeds a preset range, when the solid, powder or liquid reactant contacts the gas generated by its own chemical reaction, when the reactive molecules contact ions or other molecules which are formed by dissolving such reactive compounds in a liquid medium or solvent, and so on. Similarly, when multiple reactive compounds are required for the gas-generating chemical reaction, such compounds may be arranged to generate the gas when at least one of the reactive compounds is exposed to a proper medium such as, e.g., the air, water, and the like. The multi-compound reactant may be arranged to generate the gas by shaking or otherwise mixing such, thereby increasing contacting areas between the same or different reactive molecules, removing exterior coated layers thereof, removing or rupturing internal dividers segmenting different reactive compounds, and so on.

Although any of the foregoing gas-generating mechanisms may be employed in this invention, it is generally preferred that the reactants generate the gas when exposed to the air or moist therein or mixed with water. For example, a solid (or powder) reactant may generate the gas when exposed to air or moist or when shaken, a solid (or powder) reactant may generate the gas when mixed with a liquid reactant or liquid medium, when a liquid reactant is mixed with another liquid reactant, and so on. The reactants may also be arranged to generate the gas when foregoing reactions may take place in the presence of water, e.g, when two or more solid (or powder) reactants are mixed in water, when a solid (or powder) reactant is mixed with a liquid reactant in water, and the like.

Any nontoxic gas may be employed to drive water out of the gas-powered water guns of the present invention, although carbon dioxide (CO₂) seems by far the most preferred for such a purpose. Carbon dioxide may be relatively readily released from a variety of chemical compounds which include carbonate groups therein. For example, CO₂ may be obtained by reacting a sodium bicarbonate with a weak acid according to a reaction: NaHCO₃+weak acid->Na-salt+CO₂+(water) Other materials including therein at least one carbon dioxide-derivatives such as, e.g., CO₂, CO₃ ⁻², and HCO₃ ⁻¹, may be used as the reactive compounds to react with acids, bases, and/or other compounds so as to generate carbon dioxide through various chemical reactions, examples of which may include, but not be limited to: neutral compound with CO₂-derivative+water->CO₂+byproduct(s)  (1a) neutral compound with CO₂-derivative+strong or weak acid->CO₂+byproduct(s)  (2a) neutral compound with CO₂-derivative+strong or weak base->CO₂+byproduct(s)  (2b) acid with CO₂-derivative+water->CO₂+byproduct(s)  (3a) acid with CO₂-derivative+strong or weak acid->CO₂+byproduct(s)  (3b) acid with CO₂-derivative+strong or weak base->CO₂+byproduct(s)  (3c) base with CO₂-derivative+water->CO₂+byproduct(s)  (4a) base with CO₂-derivative+strong or weak acid->CO₂+byproduct(s)  (4b) base with CO₂-derivative+strong or weak base->CO₂+byproduct(s)  (4c) salt with CO₂-derivative+water->CO₂+byproduct(s)  (5a) salt with CO₂-derivative+strong or weak acid->CO₂+byproduct(s)  (5b) salt with CO₂-derivative+strong or weak base->CO₂+byproduct(s)  (5c) acid with CO₂-derivative+base with CO₂-derivative->CO₂+byproduct(s)  (6) It is appreciated that carbon dioxide may be obtained by other chemical reactions from other materials which may include carbon and oxygen molecules. Details of such CO₂-derivatives and other materials capable of generating CO₂, and various chemical reactions thereof are readily available in high-school and college-level chemistry textbooks and references.

Other nontoxic gases may also be employed to drive water from the gas-powered water guns of the present invention, where examples of such gases may include, but not limited to, nitrogen (N₂), helium (He), hydrogen (H₂), and the like. It is appreciated, however, that hydrogen may pose a safety hazard of explosion, though it may be readily obtained through various chemical reactions. In addition, helium may not be readily obtained by conventional chemical reactions.

When the gas-generating chemical reaction requires multiple reactive compounds, the reactant is generally arranged to include each compound in a ratio determined by a reaction stoichiometry such that at least a substantial portion of each compound is to be consumed when the chemical reaction is to be completed and that at most a negligible portion of the reactants is to remain in the gas-generation chamber. For example, each solid (or powder) reactant may be arranged to include multiple reactive compounds, where each compound may be included in a different longitudinal or radial layer or where the reactant includes multiple segregated regions each of which is homogeneously composed by one of such reactive compounds. In the alternative, such a reactant may be composed of multiple solid (or powder) reactants each dose of which may consist of, e.g., multiple pellets, capsules having powder or liquid reactive compound(s), liquid amples, and so on.

In contrary, such a reaction stoichiometry may be utilized to control rates of gas generation in the gas-generating chamber. For example, the solid, powder or liquid reactant may be arranged such that one or more of such multiple reactive compounds may be provided in an amount less than what is dictated by the reaction stoichiometry. Accordingly, the gas-generating reaction may be limited by a concentration of such a compound with a limited supply. By providing such a lacking compound as a separate solid, powder or liquid reactant, the rate and/or extent of the gas-generating reaction may be controller.

Any of the above chambers may be arranged to include at least one indicator to allow the user to monitor the amounts of water, gas, air, and/or reactants stored or remaining therein. For example, the water chamber may include a water volume indicator such as a conventional water gauge, a see-through window, and so on. The reaction chamber may also include similar solid or liquid indicators in order to allow the user to monitor the amounts of reactants and/or byproducts therein. The reaction and/or gas chamber may include conventional pressure gauges to sense the internal pressure, while the reactant chamber may include the conventional volume indicator or counter as well.

The foregoing inlets of various chambers of the water gun of this invention may be utilized for other purposes. For example, a dye (preferably washable dye) may be provided as a solid, powder or liquid article and fed to one or more chambers of such a water gun so that water dispensed from the water chamber may have a desirable color. In general, the dye may be introduced into the water chamber or along the water outlet. It is appreciated, however, that the chamber into which the dye is fed may preferably include a filter to remove undesirable materials in order to prevent clogging of the water outlet.

It is to be understood that, while various aspects and embodiments of the present invention have been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not to limit the scope of the invention, which is defined by the scope of the appended claims. Other embodiments, aspects, advantages, and modifications are within the scope of the following claims. 

1. A gas-powered water gun configured to dispense water through at least one water outlet on an user command by a pressure difference developed by gas between an interior of said water gun and atmosphere comprising: at least one water chamber which is configured to receive water, to store said water therein, to receive at least one reactant capable of generating said gas by at least one chemical reaction and developing said pressure difference, to have an airtight configuration to prevent leakage of said gas therefrom (or to maintain said pressure difference therein), and to dispense said water through said water outlet by said gas on said user command.
 2. A gas-powered water gun configured to dispense water through at least one water outlet on an user command by a pressure difference developed by gas between an interior of said water gun and atmosphere comprising: at least one water chamber configured to receive water and to store said water therein; and at least one reaction chamber which is configured to be in fluid communication with said water chamber, to receive at least one reactant which is configured to generate said gas by at least one chemical reaction, and to supply said gas at least one of directly and indirectly to said water chamber to dispense said water through said water outlet by said gas on said user command.
 3. The water gun of claim 2, wherein said gas is configured to include at least one CO₂ derivative comprising at least one of CO₂, CO₃ ⁻², and HCO₃ ⁻¹.
 4. The water gun of claim 2, wherein said reactant is configured to be formed as one of a solid reactant, a powder reactant, and a liquid reactant.
 5. The water gun of claim 4, wherein said solid reactant is configured to be provided to have a shape comprising at least one of a pellet, a bead, a sphere, a cone, an ellipsoid, and an oblong article.
 6. The water gun of claim 2, wherein said reactant is configured to be composed of a plurality of reactive compounds.
 7. The water gun of claim 6, wherein said reactant is configured to include at least two portions in each of which one of said reactive compounds is configured to be disposed and to be separated from the other of said reactive compounds.
 8. The water gun of claim 6, wherein said reactant is configured to include at least one divider configured to be disposed in at least one of an interior and exterior of said reactant and to separate at least one of said reactive compound from at least one of atmosphere and at least one of the others of said reactive compounds.
 9. The water gun of claim 2, wherein said reactant is configured to include at least one external layer of coating configured to cover at least a portion of said reactant.
 10. The water gun of claim 2, wherein said reaction chamber is said water chamber.
 11. The water gun of claim 2, wherein said reaction chamber is configured to include at least one reactant inlet which is configured to receive therethrough at least one dose of said reactant into said reaction chamber.
 12. The water gun of claim 11, wherein said reaction chamber is configured to operatively couple with said water chamber such that said reaction chamber is configured to at least one of reduce and stop to supply said gas to said water chamber when an amount of said water in said water chamber falls below a preset value.
 13. The water gun of claim 2 further comprising at least one reactant chamber which is configured to be operatively coupled to said reaction chamber, to store a plurality of doses of said reactants, and to supply at least one dose of said reactant to said reaction chamber.
 14. The water gun of claim 13, wherein said reactant chamber is configured to operatively couple with at least one of said reaction chamber and said water chamber so that said reactant chamber is configured to supply at least one dose of said reactant to said reaction chamber upon occurrence of a preset event.
 15. The water gun of claim 2 further comprising at least one gas chamber which is configured to be operatively coupled to said reaction chamber and to store at least a portion of said gas generated in said reaction chamber.
 16. The water gun of claim 15, wherein said gas chamber is configured to be disposed between said water chamber and said reaction chamber.
 17. The water gun of claim 2 further comprising at least one air pump configured to be operatively coupled to said reaction chamber in at least one of a parallel and series arrangement, to allow an user to manually compress air, and to supply compressed air to said water chamber.
 18. A method of dispensing water from a gas-powered water gun including a water chamber for storing water therein, a gas-generating chamber for generating gas, and a pressure-driving chamber to drive water out of said water chamber by said gas, said method comprising the steps of: storing water in said water chamber; generating gas by at least one chemical reaction in said gas-generating chamber, increasing pressure in said pressure-driving chamber by said gas; and dispensing said water from said water chamber by said pressure.
 19. The method of claim 18, said step of generating gas comprising the step of: adjusting an amount of said gas depending on an amount of said water in said water chamber.
 20. The method of claim 18 further comprising the step of: at least one of reducing and terminating supply of said gas to at least one of said pressure-driving chamber and said water chamber when an amount of said water in said water chamber falls below a preset value. 